Image loading optimization enhancements in 6.4

WordPress 6.4 comes with several enhancements to the wp_get_loading_optimization_attributes() function which was introduced in 6.3 as a central place to manage loading optimization attributes, specifically for images and iframes.

Quick recap: Loading optimization attributes are those such as loading="lazy" or fetchpriority="high", which can be added to certain HTMLHTML HyperText Markup Language. The semantic scripting language primarily used for outputting content in web browsers. tags to optimize loading performance in the browser.

Simplified complex logic

The logic of the wp_get_loading_optimization_attributes() is generally quite complex, as it caters for several factors that influence when to apply certain loading optimization attributes. When the function was originally introduced, it was particularly hard to follow, since it included lots of early returns as well as closures. This was mostly due to maintaining its original code paths that came from the deprecated wp_get_loading_attr_default() function as much as possible to avoid breakage.

While the function logic is still complex in WordPress 6.4, it has been notably simplified, taking a more sequential and thus easier to follow approach. This facilitated the implementation of further enhancements such as those outlined below.

Please refer to TracTrac An open source project by Edgewall Software that serves as a bug tracker and project management tool for WordPress. ticketticket Created for both bug reports and feature development on the bug tracker. #58891 for additional details on these changes.

Managing the decoding="async" attribute

The decoding="async" attribute has been present on images by default since WordPress 6.1 (see Trac ticket #53232). As of WordPress 6.4, the logic for applying the attribute has been consolidated in the wp_get_loading_optimization_attributes() function, as the attribute is a perfect fit for that function.

Deprecated function

As part of that change, the wp_img_tag_add_decoding_attr() function has been deprecated, as its logic is now incorporated into wp_img_tag_add_loading_optimization_attrs(). Unless you are using the now deprecated function in your code, no changes should be needed after this update in regards to the decoding="async" attribute. The change merely enables control over the attribute in a more consistent manner (also see the new filters introduced below).

If you are using the deprecated function and want to use a fully backward compatible replacement, you can implement a custom wrapper function such as the following:

function myplugin_img_tag_add_decoding_attr( $image, $context ) {
	global $wp_version;

	// For WP >= 6.4.
	if ( version_compare( $wp_version, '6.4', '>=' ) ) {
		$image = wp_img_tag_add_loading_optimization_attrs( $image, $context );

		// Strip potential attributes added other than `decoding="async"`.
		return str_replace(
			array(
				' loading="lazy"',
				' fetchpriority="high"',
			),
			'',
			$image
		);
	}
 
    // For WP < 6.4.
    return wp_img_tag_add_decoding_attr( $image, $context );
}

Please refer to Trac ticket #58892 for additional details on these changes.

New filters to control loading optimization attributes

With WordPress 6.4, two filters have been added to wp_get_loading_optimization_attributes() which allow modifying or completely overriding the logic used to apply the loading optimization attributes:

  • The wp_get_loading_optimization_attributes filterFilter Filters are one of the two types of Hooks https://codex.wordpress.org/Plugin_API/Hooks. They provide a way for functions to modify data of other functions. They are the counterpart to Actions. Unlike Actions, filters are meant to work in an isolated manner, and should never have side effects such as affecting global variables and output. can be used to modify the results from the WordPress coreCore Core is the set of software required to run WordPress. The Core Development Team builds WordPress. logic.
  • The pre_wp_get_loading_optimization_attributes filter can be used to use entirely custom logic and effectively short-circuit the core function by returning a value other than false.

Below are a few examples on how these two filters could be used.

Filter usage examples

You could use the wp_get_loading_optimization_attributes filter to ensure a specific image within post content receives the fetchpriority="high" attribute while other ones do not:

function set_fetchpriority_high_on_specific_image( $loading_attrs, $tag_name, $attr, $context ) {
	if ( 'img' === $tag_name ) {
		if (
			'the_content' === $context &&
			isset( $attr['src'] ) &&
			$attr['src'] === 'https://example.org/a-specific-image.jpg'
		) {
			$loading_attrs['fetchpriority'] = 'high';
		} else {
			unset( $loading_attrs['fetchpriority'] );
		}
	}
	return $loading_attrs;
}
add_filter(
	'wp_get_loading_optimization_attributes',
	'set_fetchpriority_high_on_specific_image',
	10,
	4
);

Alternatively, you could use the wp_get_loading_optimization_attributes filter to disable adding the fetchpriority="high" attribute entirely:

function disable_fetchpriority_high( $loading_attrs ) {
	unset( $loading_attrs['fetchpriority'] );
	return $loading_attrs;
}
add_filter(
	'wp_get_loading_optimization_attributes',
	'disable_fetchpriority_high'
);

You could implement entirely custom logic in a pluginPlugin A plugin is a piece of software containing a group of functions that can be added to a WordPress website. They can extend functionality or add new features to your WordPress websites. WordPress plugins are written in the PHP programming language and integrate seamlessly with WordPress. These can be free in the WordPress.org Plugin Directory https://wordpress.org/plugins/ or can be cost-based plugin from a third-party to detect which images appear in the viewport using client-side JavaScriptJavaScript JavaScript or JS is an object-oriented computer programming language commonly used to create interactive effects within web browsers. WordPress makes extensive use of JS for a better user experience. While PHP is executed on the server, JS executes within a user’s browser. https://www.javascript.com/. logic or an external service and replace the function’s default logic with that:

function override_loading_optimization_attributes( $override, $tag_name, $attr, $context ) {
	// Bail if another filter callback already overrode this.
	if ( false !== $override ) {
		return $override;
	}

	// Use custom logic to determine whether image is LCP and whether it appears above the fold.
	if ( 'img' === $tag_name ) {
		$is_lcp      = custom_function_to_detect_whether_image_is_lcp_element( $attr );
		$in_viewport = custom_function_to_detect_whether_image_is_above_the_fold( $attr );

		/*
		 * Always add `decoding="async"`.
		 * Add `fetchpriority="high"` only to the LCP image.
		 * Add `loading="lazy"` to any image below the fold / outside the viewport.
		 */
		$loading_attrs = array( 'decoding' => 'async' );
		if ( $is_lcp ) {
			$loading_attrs['fetchpriority'] = 'high';
		} elseif ( ! $in_viewport ) {
			$loading_attrs['loading'] = 'lazy';
		}
		return $loading_attrs;
	}

	return $override;
}
add_filter(
	'pre_wp_get_loading_optimization_attributes',
	'override_loading_optimization_attributes',
	10,
	4
);

Please refer to Trac ticket #58893 for additional details on these changes.

Support for custom context values

As explained in the 6.3 dev note for the wp_get_loading_optimization_attributes() function, initially it only supported specific context values used by WordPress core. This made it confusing to write custom code making use of that function as you would have been forced to use a context string used elsewhere in core in order to get the performance benefits.

This limitation has been addressed in WordPress 6.4: The function now supports arbitrary contexts, and for the most part does not apply context-specific optimizations. There are two exceptions to this which are the “template_part_header” and “get_header_image_tag” contexts. Images within these contexts will always be interpreted to be in the headerHeader The header of your site is typically the first thing people will experience. The masthead or header art located across the top of your page is part of the look and feel of your website. It can influence a visitor’s opinion about your content and you/ your organization’s brand. It may also look different on different screen sizes.. The list of these two context strings is filterable with a new wp_loading_optimization_force_header_contexts filter, which allows images with other contexts to be always assumed to appear above the fold.

Context filter usage example

Below is an example: Assume that your plugin has a particular header image rendering function where it is safe to assume any image rendered with that function appears above the fold. You can rely on an arbitrary context specific to your function and then force WordPress core to consider images with that context to appear above the fold.

function force_myplugin_special_header_context_above_the_fold( $header_contexts ) {
	$header_contexts['myplugin_special_header'] = true;
	return $header_contexts;
}
add_filter(
	'wp_loading_optimization_force_header_contexts',
	'force_myplugin_special_header_context_above_the_fold'
);

Your image rendering function then needs to call wp_get_loading_optimization_attributes( 'img', $attr, 'myplugin_special_header' ) for the above filter to take effect.

Please refer to Trac ticket #58894 for additional details on these changes.

Hook priority change for wp_filter_content_tags()

The wp_filter_content_tags() was originally introduced in WordPress 5.5 as the foundation for lazy-loading as well as other optimizations for certain tags in a content blob. More recently a problem was identified that the function is called earlier than do_shortcode(), which means that any images added by shortcodes will not be able to make use of the performance benefits from wp_filter_content_tags().

To address that limitation, the hook priority with which wp_filter_content_tags() is hooked into the various filters (“the_content”, “the_excerpt”, “widget_text_content”, and “widget_block_content”) has been changed from the default 10 to 12. For context, the do_shortcode() function has hook priority 11.

While this is technically a breaking change, careful consideration and research across the WordPress plugin directory went into this decision. No plugins in the directory are affected by this change, given that there is only limited direct usage of the wp_filter_content_tags() function, and such usage has not been specific to the core filters. Still, in case you use the wp_filter_content_tags() function directly in your code, you may want to double check that this hook priority change does not result in a problem.

If your plugin processes custom content with the wp_filter_content_tags() function, it is encouraged to call that function after parsing other content such as blocks and shortcodes. The core change will not cause problems if that is currently not the case in your code, however it is recommended to have your custom logic follow a similar order.

Please refer to Trac ticket #58853 for additional details on these changes.

Props to @westonruter and @webcommsat for review and proofreading.

#6-4, #dev-notes, #dev-notes-6-4, #performance

New option functions in 6.4

WordPress 6.4 introduces a number of new functions related to options, with a particular focus on autoloaded options.

While options are autoloaded by default, based on the $autoload parameter of add_option() and update_option(), autoloading too many options is a common cause for slow server response time as well as bugs while using a persistent object cache.

To help pluginPlugin A plugin is a piece of software containing a group of functions that can be added to a WordPress website. They can extend functionality or add new features to your WordPress websites. WordPress plugins are written in the PHP programming language and integrate seamlessly with WordPress. These can be free in the WordPress.org Plugin Directory https://wordpress.org/plugins/ or can be cost-based plugin from a third-party developers improve managing their plugins’ options, their performance, and whether to autoload them, two sets of functions are being introduced in 6.4:

  • wp_prime_option_caches() and related wrapper functions can be used to fetch multiple options with a single database query. Update: When this dev notedev note Each important change in WordPress Core is documented in a developers note, (usually called dev note). Good dev notes generally include a description of the change, the decision that led to this change, and a description of how developers are supposed to work with that change. Dev notes are published on Make/Core blog during the beta phase of WordPress release cycle. Publishing dev notes is particularly important when plugin/theme authors and WordPress developers need to be aware of those changes.In general, all dev notes are compiled into a Field Guide at the beginning of the release candidate phase. was first published, the function was named prime_options(), however that name was since revised to wp_prime_option_caches().
  • wp_set_option_autoload_values() and related wrapper functions can be used to update one or more specific options’ autoload values, independently of their option values.

New functions to retrieve multiple options in a single database query

The wp_prime_option_caches( $options ) function expects an array of option names, and then fetches any options that aren’t already cached with a single database query. The options are then stored in the cache so that subsequent get_option() calls for any of those options do not result in separate database queries.

Note that wp_prime_option_caches() does not return the options as its sole responsibility is to update the relevant caches. In order to actually retrieve multiple options at once, a new wrapper function get_options( $options ) has been introduced. It calls wp_prime_option_caches() for the option names given and then get_option() for every individual option, returning an associative array of option names and their values.

Last but not least, a third function wp_prime_option_caches_by_group() is being introduced, which primes all options of a specific option group (the mandatory first parameter of register_setting()). This can be helpful for plugins to fetch all options of a specific option group the plugin uses.

All of the above functions have been introduced not only as a performant way to retrieve multiple options from the database, but also as an alternative to autoloading options that are only needed in a few specific areas. For example, a plugin that currently autoloads a few options which are only used on the plugin’s own WP Adminadmin (and super admin) screen would be encouraged to use the new wp_prime_option_caches() or wp_prime_option_caches_by_group() instead of autoloading the options.

Example

In this example, we assume a plugin has a WP Admin screen that relies on four options: “myplugin_foo”, “myplugin_bar”, “myplugin_foobar”, and “myplugin_barfoo”. All of these options are only used on that admin screen and therefore should not be autoloaded. In other words, any add_option() and update_option() calls for those options should provide “no” for the $autoload parameter.

function myplugin_prime_admin_screen_options() {
	/*
	 * By priming the options here, no further database queries will be used
	 * when later calling `get_option()`.
	 */
	wp_prime_option_caches(
		array( 'myplugin_foo', 'myplugin_bar', 'myplugin_foobar', 'myplugin_barfoo' )
	);
}

function myplugin_add_admin_screen() {
	$hook_suffix = add_menu_page( /* Menu page arguments. */ );
	add_action( "load-{$hook_suffix}", 'myplugin_prime_admin_screen_options' );
}
add_action( 'admin_menu', 'myplugin_add_admin_screen' );

This code would ensure that the options are retrieved in a single database query. Any subsequent get_option() calls for these options would then not result in another database query and thus be extremely fast. As such, the WP Admin screen is just as performant as it would have been with autoloading those options, yet without unnecessarily slowing down performance of the entire site.

To further enhance that example, the plugin could rely on a single option group for which it registers those options. Here is the example code for that:

function myplugin_register_settings() {
	register_setting(
		'myplugin_admin_screen',
		'myplugin_foo',
		array( /* Registration arguments. */ )
	);
	register_setting(
		'myplugin_admin_screen',
		'myplugin_bar',
		array( /* Registration arguments. */ )
	);
	register_setting(
		'myplugin_admin_screen',
		'myplugin_foobar',
		array( /* Registration arguments. */ )
	);
	register_setting(
		'myplugin_admin_screen',
		'myplugin_barfoo',
		array( /* Registration arguments. */ )
	);
}
add_action( 'init', 'myplugin_register_settings' );

function myplugin_prime_admin_screen_options() {
	/*
	 * By priming the options here, no further database queries will be used
	 * when later calling `get_option()`.
	 */
	wp_prime_option_caches_by_group( 'myplugin_admin_screen' );
}

// `myplugin_add_admin_screen()` would remain as in the previous code example.

With that adjustment, the option registration would be the central place to manage the options, and the myplugin_prime_admin_screen_options() function would remain simple without maintaining a list of the exact options.

Please refer to TracTrac An open source project by Edgewall Software that serves as a bug tracker and project management tool for WordPress. ticketticket Created for both bug reports and feature development on the bug tracker. #58962 for additional details on these changes.

New functions to set option autoload values

The wp_set_option_autoload_values( array $options ) function expects an associative array of option names and their autoload values to set, and then updates those options’ autoload values in a single database query.

Additionally, two wrapper functions for the above are also being introduced for ease of use:

  • wp_set_options_autoload( $options, $autoload ) can be used to set multiple options to the same autoload value.
  • wp_set_option_autoload( $option, $autoload ) can be used to set the autoload value for a single option.

These functions can be useful in a plugin deactivation hook: After deactivation, the plugin’s options won’t be used anymore, yet they should not be deleted from the database until the user decides to uninstall the plugin.

Example

In this example, we assume a plugin has two options “myplugin_foo” and “myplugin_bar”, both of which are used in various frontend page loads and therefore autoloaded by default. To properly clean up after itself, such a plugin could implement usage of the new functions as follows:

function myplugin_activate() {
	wp_set_options_autoload(
		array( 'myplugin_foo', 'myplugin_bar' ),
		'yes'
	);
}
register_activation_hook( __FILE__, 'myplugin_activate' );

function myplugin_deactivate() {
	wp_set_options_autoload(
		array( 'myplugin_foo', 'myplugin_bar' ),
		'no'
	);
}
register_deactivation_hook( __FILE__, 'myplugin_deactivate' );

This code would ensure that the options are no longer autoloaded when the plugin has been deactivated. If the plugin gets (re-)activated, the options will be set to autoload again if they are already in the database.

Please refer to Trac ticket #58964 for additional details on these changes.

Related autoload bugbug A bug is an error or unexpected result. Performance improvements, code optimization, and are considered enhancements, not defects. After feature freeze, only bugs are dealt with, with regressions (adverse changes from the previous version) being the highest priority. fix for update_option()

While not directly tied to the above functions, it is worth noting that a bug relevant to autoloading has been addressed in 6.4: When using the $autoload parameter of update_option() alongside an option value update, the function would update the incorrect cache, not respecting the new autoload value. This could have severe implications such as returning a stale option value when the option in fact had already been deleted.

This bug has been fixed in 6.4, so that the $autoload parameter of update_option() can now be reliably used to change the option’s autoload value. It should be noted though that depending on the use-case the above functions to set option autoload values may be more suitable.

Please refer to Trac ticket #51352 for additional details on this bug fix.

Props to @westonruter and @webcommsat for review and proofreading.

#6-4, #dev-notes, #dev-notes-6-4, #performance

WordPress 6.4 Release Candidate Phase

Now that WordPress 6.4 has entered the Release Candidate phase, the following policies are in place.

These policies mainly cover how and when CoreCore Core is the set of software required to run WordPress. The Core Development Team builds WordPress. committers can commit. For non-committing contributors, this post may help explain why a Core committercommitter A developer with commit access. WordPress has five lead developers and four permanent core developers with commit access. Additionally, the project usually has a few guest or component committers - a developer receiving commit access, generally for a single release cycle (sometimes renewed) and/or for a specific component. makes a certain decision.

String Freeze

To allow the Polyglots teamPolyglots Team Polyglots Team is a group of multilingual translators who work on translating plugins, themes, documentation, and front-facing marketing copy. https://make.wordpress.org/polyglots/teams/. time to get their local language’s translationtranslation The process (or result) of changing text, words, and display formatting to support another language. Also see localization, internationalization. of WordPress ready, no new strings are permitted to be added to the release. Existing strings can be removed and/or duplicated if needed.

Seek guidance from the Polyglots team leadership for any strings reported as buggy. A buggy string is one that can not be translated to all languages in its current form. 

Tickets on the WordPress 6.4 milestone

For the remainder of the cycle, only two types of tickets may be placed on/remain on the 6.4 milestone:

  • Regressions: bugs that have been introduced during the WordPress 6.4 development cycle, either to existing or new features.
  • Test suite expansion: tests can be committed at any time without regard to code or string freezes. This can cover either new or existing features.

Trunktrunk A directory in Subversion containing the latest development code in preparation for the next major release cycle. If you are running "trunk", then you are on the latest revision. is now WordPress 6.5-alpha

WordPress 6.4 was recently forked to its own branch, and trunk is now open for commits for the next version of the software.

Backporting to the 6.4 branchbranch A directory in Subversion. WordPress uses branches to store the latest development code for each major release (3.9, 4.0, etc.). Branches are then updated with code for any minor releases of that branch. Sometimes, a major version of WordPress and its minor versions are collectively referred to as a "branch", such as "the 4.0 branch".

Backporting commits of production code (that is, anything that ends up in the zip file) now requires double sign-off by two core committers. The dev-feedback keyword should be used to request a second committer’s review, dev-reviewed should be added to indicate a second committer has reviewed and approved the commit to the 6.4 branch.

Commits to the test suite do not require double sign-off.

Props to @azaozz and @davidbaumwald for peer review.

#6-4, #6-5

Replacing hard-coded style tags with wp_add_inline_style()

This dev notedev note Each important change in WordPress Core is documented in a developers note, (usually called dev note). Good dev notes generally include a description of the change, the decision that led to this change, and a description of how developers are supposed to work with that change. Dev notes are published on Make/Core blog during the beta phase of WordPress release cycle. Publishing dev notes is particularly important when plugin/theme authors and WordPress developers need to be aware of those changes.In general, all dev notes are compiled into a Field Guide at the beginning of the release candidate phase. highlights the changes made in WordPress 6.4 to style loading. The main focus of the changes was to replace manually created style tags printed at the wp_head action with calls to wp_add_inline_style(). This change was implemented to address issues related to redundant code and bypassing the coreCore Core is the set of software required to run WordPress. The Core Development Team builds WordPress.’s style enqueuing system, which made it challenging for third-party developers to manage and control the output of style tags.

Deprecated Functions

To maintain backward compatibility, the following functions have been deprecated and replaced with the new approach:

  • print_embed_styles()
  • print_emoji_styles()
  • wp_admin_bar_header()
  • _admin_bar_bump_cb()
  • the_block_template_skip_link()

Backwards Compatibility Unhooking

Previously, when wanting to unhook certain functions like print_embed_styles() from happening at wp_print_styles(), a theme or pluginPlugin A plugin is a piece of software containing a group of functions that can be added to a WordPress website. They can extend functionality or add new features to your WordPress websites. WordPress plugins are written in the PHP programming language and integrate seamlessly with WordPress. These can be free in the WordPress.org Plugin Directory https://wordpress.org/plugins/ or can be cost-based plugin from a third-party would do:

remove_action( 'wp_print_styles', 'print_emoji_styles' );

In 6.4 this print_emoji_styles() function is now deprecated. Nevertheless, the above method for preventing emoji styles from being printed is retained, even though they are now being printed by wp_enqueue_emoji_styles(). This applies to the other deprecated functions as well, so no developer action is required.

Developer Action Required

For developers who are currently using the wp_print_styles() function, whether it’s in unit tests or within their own code, some adjustments may be necessary to ensure a smooth transition. You should follow the example set by GutenbergGutenberg The Gutenberg project is the new Editor Interface for WordPress. The editor improves the process and experience of creating new content, making writing rich content much simpler. It uses ‘blocks’ to add richness rather than shortcodes, custom HTML etc. https://wordpress.org/gutenberg/. This is what you need to do:

/**
 * Remove the deprecated `print_emoji_styles` handler.
 * It avoids breaking style generation with a deprecation message.
 */
$has_emoji_styles = has_action( 'wp_print_styles', 'print_emoji_styles' );
if ( $has_emoji_styles ) {
    remove_action( 'wp_print_styles', 'print_emoji_styles' );
}

ob_start();
wp_print_styles();
$styles = ob_get_clean();

if ( $has_emoji_styles ) {
    add_action( 'wp_print_styles', 'print_emoji_styles' );
}

This code snippet demonstrates how to handle the situation. It first checks if there’s an action hooked to wp_print_styles for print_emoji_styles(). If it does exist, it removes the action temporarily to avoid issues with style generation.

By following this approach, you can ensure that your code remains compatible with the changes introduced in this commit while avoiding any disruptions to style generation. It’s recommended to review and adjust your code accordingly if you’ve been using the wp_print_styles() function.

Exceptions

In the case of the functions for printing custom backgrounds and custom styles, converting them to use inline styles was deemed infeasible. Changing the style tagtag A directory in Subversion. WordPress uses tags to store a single snapshot of a version (3.6, 3.6.1, etc.), the common convention of tags in version control systems. (Not to be confused with post tags.) IDs in this context could potentially disrupt JavaScriptJavaScript JavaScript or JS is an object-oriented computer programming language commonly used to create interactive effects within web browsers. WordPress makes extensive use of JS for a better user experience. While PHP is executed on the server, JS executes within a user’s browser. https://www.javascript.com/. functionality for several plugins in the repository. Therefore, these functions remain unaffected by this change.

Please refer to #58775 for additional details on these changes.

Props to @spacedmonkey for writing the dev note.
Props to @westonruter, @flixos90, @webcommsat, and @bph for review and proofreading.

#6-4, #dev-notes, #dev-notes-6-4, #performance

Improvements to Object Caching in WordPress 6.4

In WordPress 6.4, the Performance team has introduced several enhancements centered around object caching, leading to better handling of filters, reduced database queries, and improved overall system efficiency. 

Change the position of notoptions lookup in get_option()

In the get_option() function, a cache lookup for the notoptions key is performed; this stores an array of keys for options known to not exist. This optimization prevents repeated database queries when certain options are requested. However, the cache lookup for notoptions was conducted before checking if the requested option exists in the cache. Given that it’s more likely that the option does exist, a change has been made to reorder the checks to first verify the option’s existence in the cache before confirming its absence. This adjustment reduces redundant queries and also eliminates an unnecessary cache lookup, improving overall performance.

Please refer to #58277 for additional details on these changes.

Improvements to WP_Query caching

Forcing split queries when object caching is enabled 

WordPress introduced the ability to perform split queries starting from version 3.1. A split query occurs when the main query in WP_Query is executed to retrieve post IDs only, rather than retrieving the entire post objects. To populate the post objects, the function _prime_post_caches() is invoked, fetching the complete post information if it is not already loaded into local memory.

Before this change, split queries were restricted to posts numbering less than 500. However, this restriction has been eliminated when persistent/external object caching is enabled. This enhancementenhancement Enhancements are simple improvements to WordPress, such as the addition of a hook, a new feature, or an improvement to an existing feature. becomes even more significant with the introduction of wp_cache_get_multiple() in WordPress coreCore Core is the set of software required to run WordPress. The Core Development Team builds WordPress.. With this function, object caches can retrieve multiple objects in a single request, offering several benefits.

Benefits of Split Queries and Object Caching:

  • Performance Improvement: Object caches, which store frequently accessed data in memory, are substantially faster than traditional database queries. By using split queries, WordPress can fetch post IDs more efficiently, reducing the load time for your website.
  • Database Offloading: The implementation of split queries alleviates the strain on the database. With only the essential post IDs selected, less data needs to be retrieved from the database, and fewer database queries are executed.
  • Primery Key Loading: The primary key for loading the post object is the focus, ensuring that the necessary data is efficiently fetched from the object cache.

In summary, the ability to perform split queries, combined with object caching, enhances WordPress’s performance and reduces the load on your database. By opting for split queries, you can enjoy faster loading times and a smoother user experience for your WordPress website.

Please refer to #57296 for additional details on these changes.

Fix caching behavior if filters are used in WP_Query

The WP_Query class in WordPress allows developers to customize queries using various filters such as posts_fields_request, posts_request, and the_posts. These filters are instrumental in modifying both the queried fields and retrieved post objects. However, there have been cases where the use of these filters could result in incomplete or invalidinvalid A resolution on the bug tracker (and generally common in software development, sometimes also notabug) that indicates the ticket is not a bug, is a support request, or is generally invalid. post objects, lacking essential data. To address this issue and ensure data consistency and integrity, a change has been introduced.

In scenarios where the posts_fields_request, posts_request, or the_posts filters are active during a query, the get_posts() method now avoids caching post objects with the usual update_post_caches() function call. Instead, it opts for a call to _prime_post_caches(). This change is designed to prevent the caching of invalid post objects, prioritizing data consistency and integrity in filtered query scenarios.

While this enhancement ensures that invalid post objects are not cached, it may occasionally trigger new database queries to prime the post data cache. Developers should be aware that this might result in slightly increased database load in specific cases.

Please refer to #58599 for additional details on these changes.

Improved performance for WP_Query for id=>parents

In WordPress 6.2, a change was made to the WP_Query class (as documented in commit [53941]) which brought forth an unforeseen issue when querying to return fields id=>parent. This issue specifically affected websites with object caching enabled, especially when dealing with a substantial number of pages. During the second execution of this query, the _prime_post_caches() function for an id=>parent query was inadvertently triggered. This led to the unnecessary priming of post, metaMeta Meta is a term that refers to the inside workings of a group. For us, this is the team that works on internal WordPress sites like WordCamp Central and Make WordPress., and term caches, even when the query only requested ID and parent information.

To address this problem and optimize query performance, a new function, _prime_post_parent_ids_caches(), has been introduced. This function is responsible for priming a dedicated cache for post parents during the initial query execution. Subsequently, the wp_cache_get_multiple() function is utilized to retrieve all post parent data in a single object cache request, ensuring a significant performance improvement. Post parent caches are invalidated when the clean_post_caches() function is called. If you are updating a post in the database, please ensure that this function is called after making this update. 

Please refer to #59188 for additional details on these changes.

Improvements to WP_Term_Query caching

New cache_results parameter in WP_Term_Query

The cache_results parameter has been introduced in WordPress to provide developers with more control over the caching behavior in WP_Term_Query queries. It allows you to determine whether or not to load results from the query cache, enabling you to obtain a complete uncached result when set to false.

The cache_results parameter is a boolean parameter, and it accepts the following values:

  • true (default): Load results from the query cache (cached results).
  • false: Retrieve a complete uncached result.

This parameter is primarily designed for developers who are working on highly custom solutions and need to bypass caching mechanisms for specific queries. In most cases, it is recommended to keep the cache_results parameter enabled (set to true) in production environments. Caching is an essential performance optimization in WordPress, and disabling it may lead to slower query execution times.

In the example above, the cache_results parameter is set to false, ensuring that the query results are retrieved without using the cache.

$args = array(
    'taxonomy' => 'category',
    'cache_results' => false, // This will fetch uncached results
);

$term_query = new WP_Term_Query($args);

The cache_results parameter in WP_Term_Query offers flexibility for developers working on specialized projects. While it can be useful in certain scenarios, exercise caution when disabling caching, as it may impact performance in a production environment. Always consider the specific requirements of your project before deciding to disable query caching.

Please refer to #52710 for additional details on these changes.

Fix caching behavior if term_clauses filters are used

When utilizing the terms_clauses or get_terms_fields filters within WP_Term_Query and the selected fields are modified, the entire term object is now cached. This change was necessary because filters can broaden the selected fields beyond just the term ID. Fields linked to the term object, such as the count or parent, may undergo modifications when queried. Caching the complete object ensures the accurate storage of these modified fields within the cache.

Please refer to #58116 for additional details on these changes.


Props to @spacedmonkey for writing, @westonruter for editing.
Props to @joemcgill, @tillkruss, @flixos90 @webcommsat for review and proofreading.

#6-4, #dev-notes, #dev-notes-6-4, #performance

Improvements to Template Loading in WordPress 6.4

Improve performance of _register_theme_block_patterns() function

The _register_theme_block_patterns() function previously introduced a substantial resource overhead issue, especially noticeable when themes, such as Twenty Twenty Four, registered a large number of blockBlock Block is the abstract term used to describe units of markup that, composed together, form the content or layout of a webpage using the WordPress editor. The idea combines concepts of what in the past may have achieved with shortcodes, custom HTML, and embed discovery into a single consistent API and user experience. patterns. This overhead was mainly due to the extensive file operations required by the function, including file system checks and file reads.

To address these performance issues, we have introduced caching using object cache in a new method called WP_Theme::get_block_patterns(). When theme development mode is disabled and a theme exists, the block patterns are stored in object cache. For sites using a persistent object cache, subsequent requests will use this cached data, eliminating the need for file lookups and reading files into memory, resulting in significant performance improvements.

It’s important to note that caches are also tied to the theme’s version number. Therefore, if you want to manually invalidate the cache, you can do so by changing the theme’s version number. This provides an additional method for cache management, especially useful during theme updates or changes.

Developers can bypass the pattern cache by enabling development mode for a theme, allowing for pattern additions and removals without the cache interfering. This is beneficial for accurate testing and development.

Cache invalidation occurs when themes are switched, the WP_Theme::cache_delete() method is called, or when the theme’s version number is updated. These mechanisms ensure that block patterns are not stored in the cache incorrectly.

Remove unnecessary checks if a theme file exists in the theme functions

In [56523] and [56357], WordPress theme functions were improved by removing unnecessary file existence checks, thereby enhancing performance and efficiency.

Background:
Previously, several functions and methods in the Themes APIAPI An API or Application Programming Interface is a software intermediary that allows programs to interact with each other and share data in limited, clearly defined ways. were designed to check for the existence of files within a child themeChild theme A Child Theme is a customized theme based upon a Parent Theme. It’s considered best practice to create a child theme if you want to modify the CSS of your theme. https://developer.wordpress.org/themes/advanced-topics/child-themes/. before falling back to the parent theme. 

However, these checks didn’t take into account whether the current theme was a child theme or not, leading to redundant file existence checks for non-child themes. This could result in unnecessary file system access and potentially slow down WordPress websites, especially in cases where there were numerous checks.

To address this issue and improve the overall performance of the Themes API, we’ve introduced an optimization that checks whether the current theme’s stylesheet directory matches the template directory before proceeding with file existence checks. This optimization significantly reduces the number of unnecessary file system accesses, as file existence checks can be resource-intensive in PHPPHP The web scripting language in which WordPress is primarily architected. WordPress requires PHP 5.6.20 or higher.

As part of this enhancementenhancement Enhancements are simple improvements to WordPress, such as the addition of a hook, a new feature, or an improvement to an existing feature., we’ve updated the following functions and methods in WordPress:

  • WP_Theme::get_file_path()
  • get_theme_file_path()
  • get_theme_file_uri()
  • locate_template()

With these optimizations in coreCore Core is the set of software required to run WordPress. The Core Development Team builds WordPress., you can expect a noticeable improvement in the performance of your WordPress theme, especially if you have a non-child theme. The reduction in unnecessary file system access can lead to faster page load times and a smoother user experience.

Tickets: #59279, #58576

Improve performance of get_block_theme_folders()

The get_block_theme_folders() function suffered from suboptimal performance due to repeated file lookups using the file_exists() function. This resulted in unnecessary I/O operations and slowed down the process of locating block template folders within themes.

To address these performance issues and improve the efficiency of the get_block_theme_folders() function, the following changes have been implemented:

  • A new method, WP_Theme::get_block_template_folders(), has been added which incorporates basic caching, storing the result in the theme’s cache, similar to how block themes are cached in the block_theme property (as outlined in [55236]). The introduction of caching significantly reduces redundant file system lookups and optimizes the overall performance of the function.
  • Improved Error Handling: This update enhances error handling by first verifying the existence of a theme before attempting to look up the file. This proactive error handling approach helps avoid unnecessary file checks and enhances the overall reliability of the function.

Impact: 

The performance enhancement in the WP_Theme::get_block_template_folders() method will lead to quicker and more efficient lookups of block template folders within themes. WordPress developers and users can anticipate improved performance, reduced I/O overhead, and a smoother experience when working with block themes.

Ticketticket Created for both bug reports and feature development on the bug tracker.: #58319

Bundled Theme: Implement the_header_image_tag() function for enhanced compatibility for older core themes.

The the_header_image_tag() function was introduced in WordPress 4.4 as part of [35594]. It is used in all themes created since WordPress 4.4 that supported headerHeader The header of your site is typically the first thing people will experience. The masthead or header art located across the top of your page is part of the look and feel of your website. It can influence a visitor’s opinion about your content and you/ your organization’s brand. It may also look different on different screen sizes. images. The function get_header_image_tag() continues to get updated with new image features, like lazy loading, async decoding and fetch priority. To ensure our core themes maintain compatibility and benefit from these enhancements, a backward compatibility shim has been applied, integrating the the_header_image_tag() function into the following core themes:

  • Twenty Ten
  • Twenty Eleven
  • Twenty Twelve
  • Twenty Fourteen
  • Twenty Sixteen

This change ensures future compatibility and modern image features are applied for header images to these older themes.

Ticket: #58675

Props to @spacedmonkey for writing this dev notedev note Each important change in WordPress Core is documented in a developers note, (usually called dev note). Good dev notes generally include a description of the change, the decision that led to this change, and a description of how developers are supposed to work with that change. Dev notes are published on Make/Core blog during the beta phase of WordPress release cycle. Publishing dev notes is particularly important when plugin/theme authors and WordPress developers need to be aware of those changes.In general, all dev notes are compiled into a Field Guide at the beginning of the release candidate phase..
Props to @westonruter for editing, @mikeschroder and @webcommsat for reviewing.

Edit: The implementation for caching theme patterns during pattern registration was changed from transients to standard object caches after this dev note was first published (See [56978]). This post has been updated to reflect those changes.

#6-4, #dev-notes, #dev-notes-6-4, #performance

Miscellaneous Editor changes in WordPress 6.4

In this dev notedev note Each important change in WordPress Core is documented in a developers note, (usually called dev note). Good dev notes generally include a description of the change, the decision that led to this change, and a description of how developers are supposed to work with that change. Dev notes are published on Make/Core blog during the beta phase of WordPress release cycle. Publishing dev notes is particularly important when plugin/theme authors and WordPress developers need to be aware of those changes.In general, all dev notes are compiled into a Field Guide at the beginning of the release candidate phase., you will find a collection of smaller changes to existing features and APIAPI An API or Application Programming Interface is a software intermediary that allows programs to interact with each other and share data in limited, clearly defined ways. updates. For component updates, please see also Updates to user-interface components in WordPress 6.4.

Updated Nov 07, 2023 to add a note on how to retrieve the full Image Light box markup in filters.


Table of Contents


Background image blockBlock Block is the abstract term used to describe units of markup that, composed together, form the content or layout of a webpage using the WordPress editor. The idea combines concepts of what in the past may have achieved with shortcodes, custom HTML, and embed discovery into a single consistent API and user experience. support

In WordPress 6.4, a new background image block support has been added, with the Group block opted-in by default. For themes using the appearanceTools feature in theme.json, the control will be available in the inspector controls, under Background.

The feature allows users to set a background image for a Group block. The selected image will be output at render-time for the block via an inline style applied to the block’s wrapper. When a background image is set, the rule background-size: cover is output along with the background-image property. This ensures that any background images adequately cover the block. Ideas for enhancements in future releases are being tracked in this GitHubGitHub GitHub is a website that offers online implementation of git repositories that can easily be shared, copied and modified by other developers. Public repositories are free to host, private repositories require a paid subscription. GitHub introduced the concept of the ‘pull request’ where code changes done in branches by contributors can be reviewed and discussed before being merged be the repository owner. https://github.com/ issue: #54336

How to add backgroundImage support to a theme

There are two ways to add support for backgroundImage to a block theme. The simplest is to opt in to the appearanceTools setting, which automatically enables a number of design tools (read more in the developer handbook).

For themes that wish to have more granular control over which UIUI User interface tools are enabled, the backgroundImage support can be opted into by setting settings.background.backgroundImage to true in theme.json. For example:

{
	"settings": {
		"background": {
			"backgroundImage": true

Note that as of WP 6.4, the backgroundImage support is only available at the individual block level, and not in global styles or at the site root.

For context and more information, view #53081.

Props to @andrewserong for the dev note (top)

FilterFilter Filters are one of the two types of Hooks https://codex.wordpress.org/Plugin_API/Hooks. They provide a way for functions to modify data of other functions. They are the counterpart to Actions. Unlike Actions, filters are meant to work in an isolated manner, and should never have side effects such as affecting global variables and output. behavior when using new Expand on Click in Image block

If your image block with `Expand on Click` enabled has Lightbox markup that you can’t seem to access from inside your filter function, below is some extra information you might need.

As of WordPress 6.4, please be aware that a built-in filter for the image block has been applied with priority 15 for images with `Expand on Click`. This means that if your filter has a priority of 15 or lower (the default is 10), then the markup used to create the Lightbox behavior will not be available to your function for processing by default.

Please make sure to use priority of at least 16 when adding filters to process the image block if you need to access the Lightbox markup.

add_filter( 'render_block_core/image', 'my_custom_html', 16 )

More information on this issue.

Props to @artemiosans and @afercia for surfacing the issue and documentation (top)

Fluid typography: configurable minimum and maximum viewport values

WordPress 6.4 introduces configurable minimum and maximum viewport width values to fluid typography settings in theme.json.Theme developers can now define their own default viewport “boundaries” for calculating fluid font sizes. These boundaries determine the browser viewport widths at which any font size clamp values will stop being “fluid”.

For example, given the following theme.jsonJSON JSON, or JavaScript Object Notation, is a minimal, readable format for structuring data. It is used primarily to transmit data between a server and web application, as an alternative to XML. settings:

"settings": { 
    "typography": { 
        "fluid": { 
            "maxViewportWidth": "800px", 
            "minViewportWidth": "600px" 
        }, 
    } 
}

Between the browser widths of 600px and 800px, a font size will be fluid, and therefore scale up or down according to the current viewport size. If the browser width is narrower than 600px or wider than 800px, the font size will no longer shrink or grow.

Due to the way the Block Editor calculates fluid font size values, maxViewportWidth and minViewportWidth only accept pxrem and em units.

In the case of unsupported values, including CSSCSS Cascading Style Sheets. variables, fallback maxViewportWidth and minViewportWidth are used –1600px and '320px' respectively.

For context and more information, view #53081.

Props to @ramonopoly for the dev note (top)

Disable layout controls from theme.json

With WordPress 6.4, it is now possible to disable layout controls globally for all blocks or on a per-block level from theme.json. This ensures that affected blocks still output their default layout styles, but the controls to edit them won’t be available in the block sidebarSidebar A sidebar in WordPress is referred to a widget-ready area used by WordPress themes to display information that is not a part of the main content. It is not always a vertical column on the side. It can be a horizontal rectangle below or above the content area, footer, header, or any where in the theme..

To disable the controls for all blocks, "allowEditing": false should be added to settings.layout, like so:

"settings": {
    "layout": {
        "allowEditing": false
    }
}

To disable the controls for individual blocks, add "allowEditing": false in settings.blocks.[block name].layout, thus:

"settings": {
    "blocks": {
        "core/cover": {
            "layout": {
                "allowEditing": false
            }
        }
    }
}

For context and more information, view  #53378. (top)

Props to @isabel_brison for above dev note (top)

RichText’s multiline prop replaces with simple multiple instances

RichText‘s multiline prop has been deprecated since 6.1 and was scheduled for removal in 6.3. We’re leaving the deprecated prop in place, but its functionality has been simplified internally, so you may experience changes.

Instead of one large rich text field, each line is now its own rich text field. Contributors added a splitting and merging functionality, so the fallback is gracious, but some things like paste may work differently. It’s worth noting that this prop remains deprecated and all block authors are encouraged to use InnerBlocks instead.

For context and more information, view #54310.

Props to @ellatrix for the above dev note (top)

New public hook in the Block Editor API: useBlockEditingMode()

Blocks can set an editing “mode” using the useBlockEditingMode hook. useBlockEditingMode() allows a block to restrict the user interface that is displayed for editing that block and its inner blocks.

The block editing mode can be one of three options:

  • 'disabled': Prevents editing the block entirely, that is, it cannot be selected.
  • 'contentOnly': Hides all non-content UI, for example, auxiliary controls in the toolbar, the block movers, block settings.
  • 'default': Allows editing the block as normal.

The block editing mode is inherited by all the block’s inner blocks, unless inner blocks have their own modes set.

Usage:

function MyBlock( { attributes, setAttributes } ) { 
     useBlockEditingMode( 'disabled' ); 
     // MyBlock will be marked as 'disabled' editing mode. 
     return ; 
}

useBlockEditingMode() also returns a block’s current editing mode, which can be utilized to further configure block properties. For example, a component inheriting its parent’s block editing mode:

function ChildComponent( props ) { 
     const blockEditingMode = useBlockEditingMode(); 
     let text = 'Child component'; 
     if ( blockEditingMode === 'disabled' ) { 
     // Block is disabled, add custom block properties to indicate disabled mode.
          text+= ' is disabled!'; 
     } 

    if ( blockEditingMode === 'default' ) {
       // Block can be edited, show controls or other editing-related settings.     \
         
    } 
   return 
{ text }
; }

For context and more information, view #52094.

Props to @ramonopoly for above dev note (top)

Three experimental APIs were stabilized in WordPress 6.4. That means they should be safe from backward-compatibility issues when you use them in production:

  • defaultBlock
  • directInsert
  • getDirectInsertBlock

More information on GitHub #52083. The documentation on Nested Blocks reflects the updates.

Props to @smrubenstein for dev note (top)

Introduce SCRIPT_DEBUG to make package compatibile with Webpack 5

This change in WordPress coreCore Core is the set of software required to run WordPress. The Core Development Team builds WordPress. is mostly an internal optimization to send less code to the browser. It could be useful for developers using @wordpress/scripts that it is possible to hide code behind this debug flag.

if ( typeof SCRIPT_DEBUG !== 'undefined' && SCRIPT_DEBUG === true ) {
    // This code runs only in the development mode and gets completely removed from the production build.
}

For context and more information, view #50122.

Props to @gziolo for above dev note (top)

Add edits data to the useEntityRecord

Now, the useEntityRecord adds to its output a key called edits containing the nonTransientEdits of an entity record. A code example

const widget = useEntityRecord( 'root', 'widget', 1 ); 
widget.edit( { hello: 'foo' } );

Expected result:

{ edits: { hello: 'foo' } ... }

For context and more information, view #541673.

Props to @mmaattiiaass for above dev note (top)


Props for review of the full post to @webcommsat and @priethor

#6-4, #dev-notes, #dev-notes-6-4

Script loading changes in WordPress 6.4

Script loading strategies are now employed in coreCore Core is the set of software required to run WordPress. The Core Development Team builds WordPress. and bundled themes to improve performance of loading scripts with defer and async attributes. Additionally, scripts on the frontend and login screen are now constructed using script helper functions, making it possible to utilize Content Security Policy to harden against any XSS vulnerabilities. This change also has back-compat implications for the obsolete use of the clean_url filterFilter Filters are one of the two types of Hooks https://codex.wordpress.org/Plugin_API/Hooks. They provide a way for functions to modify data of other functions. They are the counterpart to Actions. Unlike Actions, filters are meant to work in an isolated manner, and should never have side effects such as affecting global variables and output. to inject defer and async attributes; plugins should now use the script loading strategies APIAPI An API or Application Programming Interface is a software intermediary that allows programs to interact with each other and share data in limited, clearly defined ways. instead. The full details follow.

Utilizing script loading strategies

In WordPress 6.3, the script loading strategies were introduced (#12009), enabling scripts to finally have an API for marking them to be printed with async or defer without resorting to filtering script_loader_tag (or worse clean_url, per below). For more information, refer to the dev note on Registering scripts with async and defer attributes in WordPress 6.3.

In WordPress 6.4, script loading strategies are now being employed for frontend scripts in core and bundled themes. For the most part, the defer loading strategy is used since it is more consistent in its loading behavior, in that a defer script always executes once the DOM has loaded; a script with `async` may actually blockBlock Block is the abstract term used to describe units of markup that, composed together, form the content or layout of a webpage using the WordPress editor. The idea combines concepts of what in the past may have achieved with shortcodes, custom HTML, and embed discovery into a single consistent API and user experience. rendering if it is already cached. 

Additionally, scripts now loading with defer have been moved from the footer to the head so that they are discovered earlier while the document is loading and can execute sooner once the document is loaded. The changes include:

  • The defer loading strategy is being used for all block view scripts, such as the Navigation, File, and Search blocks as well as any blocks added by plugins. (#59115)
  • The defer loading strategy is also now being used for the wp-embed script which is included when there is a WordPress post embed present on the page. (#58931)
  • Frontend scripts used in bundled themes also use the defer loading strategy. (#59316)
  • The async loading strategy is used for the comment-reply script, and it continues to load in the footer since it is low priority being that comments are not visible when first viewing a post. (#58870)

If there is any theme or pluginPlugin A plugin is a piece of software containing a group of functions that can be added to a WordPress website. They can extend functionality or add new features to your WordPress websites. WordPress plugins are written in the PHP programming language and integrate seamlessly with WordPress. These can be free in the WordPress.org Plugin Directory https://wordpress.org/plugins/ or can be cost-based plugin from a third-party that enqueues a script that depends on any of the above scripts (which is unlikely), the script loading strategy API considers the dependents of a delayed script so that if any of them are blocking, the delayed script will also fall back to blocking. This ensures the execution order is preserved.

Eliminating manual construction of script tags

Throughout WordPress core there have been many places where script tags are manually constructed instead of relying on the helper functions wp_print_inline_script_tag(), wp_get_inline_script_tag(), wp_print_script_tag(), and wp_get_script_tag(). In WordPress 6.4 via #58664, these functions are now employed for all scripts printed to the frontend and for scripts printed on the login screen. This includes all scripts printed via wp_enqueue_script() as well as other functions that interact with WP_Scripts, namely wp_add_inline_script() and wp_localize_script(). More details on  #59446 which continues this work throughout wp-adminadmin (and super admin).

Using these helper functions makes core easier to read and maintain with less code duplication. It also opens the door to being able to leverage Content Security Policy (CSP) for hardening WordPress against script injection attacks (XSS vulnerabilities). This is due to these functions allowing additional attributes to be added to script tags via the wp_script_attributes and wp_inline_script_attributes filters, allowing the nonce attribute to be added. Refer to an example plugin that enables Strict CSP on the frontend and login screens.

On a related note to the script loading strategies above, there is one aspect of this change that breaks a prior method for adding async or defer to scripts using the clean_url filter:

<?php
// ⚠ WARNING: Do not do this.
function defer_parsing_of_js ( $url ) {
    if ( FALSE === strpos( $url, '.js' ) ) return $url;
    if ( strpos( $url, 'jquery.js' ) ) return $url;
    return "$url' defer ";
}
add_filter( 'clean_url', 'defer_parsing_of_js', 11, 1 );

This no longer works with WordPress 6.4 because the script URLURL A specific web address of a website or web page on the Internet, such as a website’s URL www.wordpress.org is now escaped when constructing the HTMLHTML HyperText Markup Language. The semantic scripting language primarily used for outputting content in web browsers. attributes for the script tagtag A directory in Subversion. WordPress uses tags to store a single snapshot of a version (3.6, 3.6.1, etc.), the common convention of tags in version control systems. (Not to be confused with post tags.). So previously if it resulted in this script tag:

<script src='/wp-includes/js/underscore.js?ver=1.13.4' defer></script>

It now results in:

<script src="/wp-includes/js/underscore.js?ver=1.13.4%27%20defer"></script>

The clean_url filter (introduced in WP 2.3) never should have been used for this purpose once the script_loader_tag filter was introduced in WP 4.1. The clean_url filter runs on every single URL on the page, not just the script URLs. Also, the clean_url filter approach relied on scripts being printed with single-quoted HTML attribute values. 

Plugins continuing to use the clean_url filter in this way will find that the desired attribute is no longer injected, and that the attribute instead appears appended to the ver query parameter for the script. Plugins seeking to add defer or async attributes should instead now use the script loading strategies API. More on the dev notedev note Each important change in WordPress Core is documented in a developers note, (usually called dev note). Good dev notes generally include a description of the change, the decision that led to this change, and a description of how developers are supposed to work with that change. Dev notes are published on Make/Core blog during the beta phase of WordPress release cycle. Publishing dev notes is particularly important when plugin/theme authors and WordPress developers need to be aware of those changes.In general, all dev notes are compiled into a Field Guide at the beginning of the release candidate phase. Registering scripts with async and defer attributes in WordPress 6.3

Props to @webcommsat and @flixos90 for reviewing.

#6-4, #dev-notes, #dev-notes-6-4

Changes to attachment pages

As of WordPress 6.4, attachment pages for new WordPress installations are fully disabled.

Until WordPress 6.4 was released, WordPress created attachment pages by default for every attachment uploaded. On the vast majority of sites, these attachment pages don’t add any meaningful information. They do, however, exist, get indexed by search engines, and sometimes even rank in search results, leading to bad results for users and site owners.

This change introduces a wp_attachment_pages_enabled database option to control the attachment pages’ behavior:

  • On existing sites, the option is set to 1 on upgrade, so that attachment pages continue to work as is.
  • For new sites, the option is set to 0 by default, which means attachment pages are redirected to the attachment URLURL A specific web address of a website or web page on the Internet, such as a website’s URL www.wordpress.org.
  • Sites administrators who want to enable or disable the attachment pages can set the option to 1 or 0, respectively.

When attachment pages are disabled, the adminadmin (and super admin) link “View attachment page” changes to “View Media File”.

Setting the option

Via WP CLICLI Command Line Interface. Terminal (Bash) in Mac, Command Prompt in Windows, or WP-CLI for WordPress.

To test this change or if you just want to change it on a live site, you can use WP CLI. You would do so like this:

wp option set wp_attachment_pages_enabled 0|1

Via a pluginPlugin A plugin is a piece of software containing a group of functions that can be added to a WordPress website. They can extend functionality or add new features to your WordPress websites. WordPress plugins are written in the PHP programming language and integrate seamlessly with WordPress. These can be free in the WordPress.org Plugin Directory https://wordpress.org/plugins/ or can be cost-based plugin from a third-party

Another option is to use this small plugin built by @costdev during the development process that allows enabling the attachment pages through an admin bar item.

Via the admin options page

While this is not usually recommended, you can visit wp-admin/options.php on your site, search for wp_attachment_pages_enabled and change the option right there.

TracTrac An open source project by Edgewall Software that serves as a bug tracker and project management tool for WordPress. ticketticket Created for both bug reports and feature development on the bug tracker. #57913

Props to @joostdevalk for writing the dev notedev note Each important change in WordPress Core is documented in a developers note, (usually called dev note). Good dev notes generally include a description of the change, the decision that led to this change, and a description of how developers are supposed to work with that change. Dev notes are published on Make/Core blog during the beta phase of WordPress release cycle. Publishing dev notes is particularly important when plugin/theme authors and WordPress developers need to be aware of those changes.In general, all dev notes are compiled into a Field Guide at the beginning of the release candidate phase..

Props to @sabernhardt @bph and @webcommsat for peer review.

#6-4, #dev-notes, #dev-notes-6-4

Introducing admin notice functions in WordPress 6.4

Adminadmin (and super admin) notices are widely used within WordPress CoreCore Core is the set of software required to run WordPress. The Core Development Team builds WordPress. and in the extender community. Admin notices have common markup patterns and CSSCSS Cascading Style Sheets. classes, but required maintaining HTMLHTML HyperText Markup Language. The semantic scripting language primarily used for outputting content in web browsers. independently for each notice throughout a project.

In #57791, two new functions were proposed: wp_get_admin_notice() and wp_admin_notice().

These functions abstract the HTML markup generation to reduce the maintenance burden, encourage consistency, and enable argument and message filtering for all admin notices. In addition, a new wp_admin_notice action has been introduced, which fires before a notice is output.

New functions

wp_get_admin_notice()

  • Returns the markup for an admin notice.
  • Note: The markup is not fully escaped and care should be taken to select the appropriate escaping function before output.

wp_admin_notice()

  • Outputs the markup for an admin notice.
  • Markup is created using wp_get_admin_notice() and escaped using wp_kses_post() before output.

Parameters

Both functions have the following parameters:

  • string $message The message for the notice.
  • array $args An array of arguments for the notice.
    • string $type Optional. The type of admin notice. This will be appended to 'notice-' to create the HTML class name. For example, a type of 'success' will produce a 'notice-success' HTML class. Default empty string.
    • bool $dismissible Optional. Whether the notice is dismissible. Default false.
    • string $id Optional. The value for the HTML id attribute. Default empty string.
    • array $additional_classes Optional. An array of additional class names to use for the notice. These are used as provided. Default empty array.
    • array $attributes Optional. An associative array of HTML attributes for the notice. Boolean true attributes may just include the name of the attribute. Default empty array.
    • bool $paragraph_wrap Optional. Whether to wrap the message in <p></p> tags. Default true.

Filters

wp_get_admin_notice() applies the following filters:

  • wp_admin_notice_args – Filters the arguments for an admin notice.
    • Passed arguments: array $args, string $message
  • wp_admin_notice_markup – Filters the markup for an admin notice.
    • Passed arguments: string $markup, string $message, array $args

Actions

wp_admin_notice() fires the following action:

  • wp_admin_notice – Fires before an admin notice is output.
    • Passed arguments: string $message, array $args

Example usage

Output a dismissible success notice

wp_admin_notice(
  __( 'Plugin update failed.', 'my-text-domain' ),
  array(
    'type'               => 'error',
    'dismissible'        => true,
    'additional_classes' => array( 'inline', 'notice-alt' ),
    'attributes'         => array( 'data-slug' => 'plugin-slug' )
  )
);

Result

<div class="notice notice-error is-dismissible inline notice-alt" data-slug="plugin-slug"><p>Plugin update failed.</p></div>

Create a collection of notices to output at once 

$output = '';
foreach ( $success_messages as $message ) {
  $output .= wp_get_admin_notice(
    $message,
    array( 'type' => 'success' )
  );
}

echo wp_kses_post( $output );

Result

<div class="notice notice-success"><p>Success message 1</p></div>

(repeated for each notice)

Add a class to every ‘warning’ admin notice

add_filter( 'wp_admin_notice_args', 'myprefix_add_class_to_warnings' );
function myprefix_add_class_to_warnings( $args ) {
  if ( 'warning' === $args['type'] ) {
    $args['additional_classes'][] = 'my-class';
  }

  return $args;
}

Result

<div class="notice notice-warning my-class"><p>Warning message 1</p></div>

(repeated for each warning notice)

Usage in WordPress Core

The new admin notice functions have been implemented in most locations in WordPress Core. Further work will be done in WordPress 6.5 to complete the process and migrate older notices (using the 'updated' and 'error' classes) to the current admin notice pattern ('notice-success', 'notice-info', 'notice-warning', and 'notice-error').

Props to @joedolson and @webcommsat for peer review.

#6-4, #dev-notes, #dev-notes-6-4