Title: 2021 – Page 20 – Make WordPress Core --- # Yearly Archives: 2021 [ ](https://profiles.wordpress.org/audrasjb/) [Jb Audras](https://profiles.wordpress.org/audrasjb/) 7:35 pm _on_ August 24, 2021 Tags: [5.8.1 ( 8 )](https://make.wordpress.org/core/tag/5-8-1/), [5.9 ( 104 )](https://make.wordpress.org/core/tag/5-9/), [core ( 743 )](https://make.wordpress.org/core/tag/core/), [week in core ( 245 )](https://make.wordpress.org/core/tag/week-in-core/)    # 󠀁[A Week in Core – August 23, 2021](https://make.wordpress.org/core/2021/08/24/a-week-in-core-august-23-2021/)󠁿 Welcome back to a new issue of _Week in CoreCore Core is the set of software required to run WordPress. The Core Development Team builds WordPress._. Let’s take a look at what changed on TracTrac An open source project by Edgewall Software that serves as a bug tracker and project management tool for WordPress. between August 16 and August 23, 2021. * 27 commits * 21 contributors * 58 tickets created * 5 tickets reopened * 43 tickets closed Pending the appointment of the WordPress 5.9 team, a number of tickets have been fixed, waiting for the next minor and major releasemajor release A release, identified by the first two numbers (3.6), which is the focus of a full release cycle and feature development. WordPress uses decimaling count for major release versions, so 2.8, 2.9, 3.0, and 3.1 are sequential and comparable in scope.(s). Ticketticket Created for both bug reports and feature development on the bug tracker. numbers are based on the [Trac timeline for the period above](https://core.trac.wordpress.org/timeline?from=08%2F23%2F2021&daysback=7&authors=&ticket=on&changeset=on&repo-=on&repo-design=on&repo-tests=on&sfp_email=&sfph_mail=&update=Update). The following is a summary of commits, organized by component and/or focus. ## Code changes ### Build/Test Tools * Include the commit short summary in SlackSlack Slack is a Collaborative Group Chat Platform [https://slack.com/](https://slack.com/). The WordPress community has its own Slack Channel at [https://make.wordpress.org/chat/](https://make.wordpress.org/chat/) messages – [#52644](https://core.trac.wordpress.org/ticket/52644) * Move loading the `PO` class to `set_up_before_class()` – [#53363](https://core.trac.wordpress.org/ticket/53363) * Move loading the `WP_Community_Events` class to `set_up_before_class()` – [#53363](https://core.trac.wordpress.org/ticket/53363) * Rename classes in `phpunit/tests/admin/` per the naming conventions – [#53363](https://core.trac.wordpress.org/ticket/53363) * Rename classes in `phpunit/tests/editor/` per the naming conventions – [#53363](https://core.trac.wordpress.org/ticket/53363) * Rename classes in `phpunit/tests/error-protection/` per the naming conventions– [#53363](https://core.trac.wordpress.org/ticket/53363) * Rename classes in `phpunit/tests/feed/` per the naming conventions – [#53363](https://core.trac.wordpress.org/ticket/53363) * Rename classes in `phpunit/tests/formatting/` per the naming conventions – [#53363](https://core.trac.wordpress.org/ticket/53363) * Use a better return type check for `parse_url()` in `do_enclose()` tests – [#53635](https://core.trac.wordpress.org/ticket/53635) ### Code Modernization * Check the input type in `validate_file()` – [#53635](https://core.trac.wordpress.org/ticket/53635) * Check the return type of `parse_url()` in `WP::parse_request()` – [#53635](https://core.trac.wordpress.org/ticket/53635) * Check the return type of `parse_url()` in `download_url()` – [#53635](https://core.trac.wordpress.org/ticket/53635) * Check the return type of `parse_url()` in `ms_cookie_constants()` – [#53635](https://core.trac.wordpress.org/ticket/53635) * Check the return type of `parse_url()` on 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/](https://wordpress.org/plugins/) or can be cost-based plugin from a third-party./Theme Editor screens – [#53635](https://core.trac.wordpress.org/ticket/53635) * Correct handling of `null` in `wp_parse_str()` – [#53635](https://core.trac.wordpress.org/ticket/53635) * Only set `auto_detect_line_endings` in PHPPHP The web scripting language in which WordPress is primarily architected. WordPress requires PHP 7.4 or higher < 8.1– [#53635](https://core.trac.wordpress.org/ticket/53635) * Pass correct default value to `http_build_query()` in `WP_Sitemaps_Provider:: get_sitemap_url()` – [#53635](https://core.trac.wordpress.org/ticket/53635) * Silence the deprecation warning for `auto_detect_line_endings` – [#53635](https://core.trac.wordpress.org/ticket/53635) ### Customize * Hide native control on background position field – [#53803](https://core.trac.wordpress.org/ticket/53803) ### Editor * Replace the remaining references to `wp.editor` with `wp.oldEditor` – [#53762](https://core.trac.wordpress.org/ticket/53762) ### External Libraries * Restore the `phpcs:ignore` statements in PHPMailer – [#53953](https://core.trac.wordpress.org/ticket/53953) * Upgrade PHPMailer to version 6.5.1 – [#53953](https://core.trac.wordpress.org/ticket/53953) ### Media * Check the return type of `_get_cron_array()` in `WP_Media_List_Table::prepare_items()`– [#53949](https://core.trac.wordpress.org/ticket/53949) * Fix layout of media library modal on narrow screens – [#53679](https://core.trac.wordpress.org/ticket/53679) * Increase number of media items displayed per page – [#53827](https://core.trac.wordpress.org/ticket/53827) ### Privacy * Add space below page selector – [#53782](https://core.trac.wordpress.org/ticket/53782) ### REST APIREST API The REST API is an acronym for the RESTful Application Program Interface (API) that uses HTTP requests to GET, PUT, POST and DELETE data. It is how the front end of an application (think “phone app” or “website”) can communicate with the data store (think “database” or “file system”) 󠀁[https://developer.wordpress.org/rest-api/](https://developer.wordpress.org/rest-api/)󠁿 * Remove trailing slashes when preloading requests and add unit tests for it – [#51636](https://core.trac.wordpress.org/ticket/51636) ### Toolbar * Limit the icon transition style to color only – [#43423](https://core.trac.wordpress.org/ticket/43423) ## Props **Thanks to the 21 people who contributed to WordPress Core on Trac last week:** [@jrf](https://profiles.wordpress.org/jrf/) (10), [@SergeyBiryukov](https://profiles.wordpress.org/sergeybiryukov/)( 9), [@hellofromTonya](https://profiles.wordpress.org/hellofromtonya/) (8), [@mukesh27](https://profiles.wordpress.org/mukesh27/)( 4), [@sabernhardt](https://profiles.wordpress.org/sabernhardt/) (3), [@joedolson](https://profiles.wordpress.org/joedolson/)( 2), [@zieladam](https://profiles.wordpress.org/zieladam/) (2), [@audrasjb](https://profiles.wordpress.org/audrasjb/)( 2), [@earnjam](https://profiles.wordpress.org/earnjam/) (1), [@moch11](https://profiles.wordpress.org/moch11/)( 1), [@desrosj](https://profiles.wordpress.org/desrosj/) (1), [@andraganescu](https://profiles.wordpress.org/andraganescu/)( 1), [@wb1234](https://profiles.wordpress.org/wb1234/) (1), [@walbo](https://profiles.wordpress.org/walbo/)( 1), [@antpb](https://profiles.wordpress.org/antpb/) (1), [@AlGala](https://profiles.wordpress.org/algala/)( 1), [@ravipatel](https://profiles.wordpress.org/ravipatel/) (1), [@antonvlasenko](https://profiles.wordpress.org/antonvlasenko/)( 1), [@johnjamesjacoby](https://profiles.wordpress.org/johnjamesjacoby/) (1), [@guillaumeturpin](https://profiles.wordpress.org/guillaumeturpin/)( 1), and [@lucatume](https://profiles.wordpress.org/lucatume/) (1). **Congrats and welcome to our 5 new contributors of the week! **[@moch11](https://profiles.wordpress.org/moch11/), [@wb1234](https://profiles.wordpress.org/wb1234/), [@AlGala](https://profiles.wordpress.org/algala/), [@antonvlasenko](https://profiles.wordpress.org/antonvlasenko/), and [@guillaumeturpin](https://profiles.wordpress.org/guillaumeturpin/) ♥️ **Core committers:** [@sergeybiryukov](https://profiles.wordpress.org/sergeybiryukov/)( 19), [@peterwilsoncc](https://profiles.wordpress.org/peterwilsoncc/) (3), [@azaozz](https://profiles.wordpress.org/azaozz/)( 2), [@ryelle](https://profiles.wordpress.org/ryelle/) (2), and [@desrosj](https://profiles.wordpress.org/desrosj/)( 1). [#5-8-1](https://make.wordpress.org/core/tag/5-8-1/), [#5-9](https://make.wordpress.org/core/tag/5-9/), [#core](https://make.wordpress.org/core/tag/core/), [#week-in-core](https://make.wordpress.org/core/tag/week-in-core/) [ ](https://profiles.wordpress.org/francina/) [Francesca Marano](https://profiles.wordpress.org/francina/) 6:12 pm _on_ August 24, 2021 Tags: [agenda ( 1,141 )](https://make.wordpress.org/core/tag/agenda/), [core ( 743 )](https://make.wordpress.org/core/tag/core/), [dev chat ( 920 )](https://make.wordpress.org/core/tag/dev-chat/) # 󠀁[Dev Chat Agenda for August 25, 2021](https://make.wordpress.org/core/2021/08/24/dev-chat-agenda-for-august-25-2021/)󠁿 Here is the agenda for this week’s developer meeting to occur at [August 25, 2021, at 20:00 UTC](https://www.timeanddate.com/worldclock/fixedtime.html?iso=20210825T2000). ## Blogblog (versus network, site) Post Highlights and announcements Bringing to your attention some interesting reads and some call for feedback and/ or volunteers * [@desrosj](https://profiles.wordpress.org/desrosj/) and [@circlecube](https://profiles.wordpress.org/circlecube/) will form the squad for 5.8.x releases. _Edited to add:_ [Here is the 5.8.1 schedule](https://make.wordpress.org/core/2021/08/24/wordpress-5-8-x-release-team-and-5-8-1-schedule/). Thanks! * _Edited to Add_: [A Week in Core – August 23, 2021](https://make.wordpress.org/core/2021/08/24/a-week-in-core-august-23-2021/). Thanks [@audrasjb](https://profiles.wordpress.org/audrasjb/) * First 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. for WordPress 5.9 is out: [Gallery Block Refactor Dev Note](https://make.wordpress.org/core/2021/08/20/gallery-block-refactor-dev-note/) * [Navigation Editor Hallway Hangout: compare/contrast the old and new screens](https://make.wordpress.org/core/2021/08/19/navigation-editor-hallway-hangout-compare-contrast-the-old-and-new-screens/)– the session was held on August 24th and you can already see the progress made in the related [Spreadsheet](https://docs.google.com/spreadsheets/d/1UB6fMaPmQPGr-xf_R0-P3Mjef_Fhe7UJOBc0dir1GjA/edit#gid=0). _Edited to Add_: video recording and additional resources were [posted](https://make.wordpress.org/core/2021/08/25/hallway-hangout-summary-compare-and-contrast-the-navigation-screens/) today! * [Gutenberg 11.3 is out](https://make.wordpress.org/core/2021/08/18/whats-new-in-gutenberg-11-3-18-august/). Thanks [@vcanales](https://profiles.wordpress.org/vcanales/) for the write up. ## Components check-in and status updates * Check-in with each component for status updates. * Poll for components that need assistance. ## Open Floor Do you have something to propose for the agenda, or a specific item relevant to the usual agenda items above? Please leave a comment, and say whether or not you’ll be in the chat, so the group can either give you the floor or bring up your topic for you accordingly. This meeting happens in the [#core](https://wordpress.slack.com/messages/C02RQBWTW) channel. To join the meeting, you’ll need an account on the [Making WordPress Slack](https://make.wordpress.org/chat/). [#agenda](https://make.wordpress.org/core/tag/agenda/), [#core](https://make.wordpress.org/core/tag/core/), [#dev-chat](https://make.wordpress.org/core/tag/dev-chat/) [ ](https://profiles.wordpress.org/paaljoachim/) [Paal Joachim Romdahl](https://profiles.wordpress.org/paaljoachim/) 3:03 pm _on_ August 24, 2021 Tags: [agenda ( 1,141 )](https://make.wordpress.org/core/tag/agenda/), [core-editor ( 756 )](https://make.wordpress.org/core/tag/core-editor/), [core-editor-agenda ( 189 )](https://make.wordpress.org/core/tag/core-editor-agenda/), [meeting ( 405 )](https://make.wordpress.org/core/tag/meeting/)    # 󠀁[Editor Chat Agenda: 25 August 2021](https://make.wordpress.org/core/2021/08/24/editor-chat-agenda-25-august-2021/)󠁿 Facilitator and notetaker: [@paaljoachim](https://profiles.wordpress.org/paaljoachim/) This is the agenda for the weekly _editor chat_ scheduled for [Wednesday, August ](https://www.timeanddate.com/worldclock/fixedtime.html?msg=Core+Editor+Meeting&iso=20210825T16&p1=187&ah=1) [25, 2021, 04:00 PM GMT+1](https://www.timeanddate.com/worldclock/fixedtime.html?msg=Core+Editor+Meeting&iso=20210825T16&p1=187&ah=1). _This meeting is held in the [#core-editor](https://wordpress.slack.com/messages/C02QB2JS7) channel in the Making WordPress SlackSlack Slack is a Collaborative Group Chat Platform [https://slack.com/](https://slack.com/). The WordPress community has its own Slack Channel at [https://make.wordpress.org/chat/](https://make.wordpress.org/chat/)._ * [What’s new in Gutenberg (11.3)](https://make.wordpress.org/core/2021/08/18/whats-new-in-gutenberg-11-3-18-august/) * [Whats next in Gutenberg: July and August.](https://make.wordpress.org/core/2021/07/21/whats-next-in-gutenberg-site-editing-status-check-late-july-august-2021/) * Updates based on [updated scope for site editing projects](https://github.com/WordPress/gutenberg/issues/33094) and WP 5.8: - Navigation 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. & Navigation Editor. * - Template editor. - Patterns. - Styling. - Mobile Team. * Task Coordination. * Open Floor. If you are not able to attend the meeting, you are encouraged to share anything relevant for the discussion: * If you have anything to share for the Task Coordination section, please leave it as a comment on this post. * If you have anything to propose for the agenda or other specific items related to those listed above, please leave a comment below. [#agenda](https://make.wordpress.org/core/tag/agenda/), [#core-editor](https://make.wordpress.org/core/tag/core-editor/), [#core-editor-agenda](https://make.wordpress.org/core/tag/core-editor-agenda/), [#meeting](https://make.wordpress.org/core/tag/meeting/) [ ](https://profiles.wordpress.org/francina/) [Francesca Marano](https://profiles.wordpress.org/francina/) 2:09 pm _on_ August 24, 2021 Tags: [core-auto-updates ( 37 )](https://make.wordpress.org/core/tag/core-auto-updates/), [updater ( 21 )](https://make.wordpress.org/core/tag/updater/), [upgrade-install ( 32 )](https://make.wordpress.org/core/tag/upgrade-install/) # 󠀁[Upgrade/Install component meeting agenda for August 24, 2021](https://make.wordpress.org/core/2021/08/24/upgrade-install-component-meeting-agenda-for-august-17-2021-2/)󠁿 The next meeting is scheduled on [Tuesday, August 24, 2021, at 17:00 UTC](https://www.timeanddate.com/worldclock/fixedtime.html?iso=20210824T1700) and will take place on [#core-auto-updates](https://wordpress.slack.com/archives/CULBN711P/p1583863308013300) SlackSlack Slack is a Collaborative Group Chat Platform [https://slack.com/](https://slack.com/). The WordPress community has its own Slack Channel at [https://make.wordpress.org/chat/](https://make.wordpress.org/chat/) channel. The aim of the chat is to check the status of the [rollback for failed plugin/theme updates](https://core.trac.wordpress.org/ticket/51857) after last Friday’s testing session and triagetriage The act of evaluating and sorting bug reports, in order to decide priority, severity, and other factors./scrub tickets in the component. Got something to propose for the agenda? Please leave a comment below. See you later! [#core-auto-updates](https://make.wordpress.org/core/tag/core-auto-updates/), [#updater](https://make.wordpress.org/core/tag/updater/), [#upgrade-install](https://make.wordpress.org/core/tag/upgrade-install/) [ ](https://profiles.wordpress.org/danfarrow/) [Dan Farrow](https://profiles.wordpress.org/danfarrow/) 2:50 pm _on_ August 21, 2021 Tags: [core-css ( 191 )](https://make.wordpress.org/core/tag/core-css/), [summary ( 975 )](https://make.wordpress.org/core/tag/summary/)    # 󠀁[CSS Chat Summary: 19 August 2021](https://make.wordpress.org/core/2021/08/21/css-chat-summary-19-august-2021/)󠁿 [The meeting took place here on Slack](https://wordpress.slack.com/archives/CQ7V4966Q/p1629407112134300). [@dryanpress](https://profiles.wordpress.org/dryanpress/) facilitated and [@danfarrow](https://profiles.wordpress.org/danfarrow/) wrote up these notes. ## CSSCSS Cascading Style Sheets. Custom Properties (󠀁[#49930](https://core.trac.wordpress.org/ticket/49930)󠁿) * [@dryanpress](https://profiles.wordpress.org/dryanpress/) outlined the goal of the project: To replace hard-coded colors in WordPress CoreCore Core is the set of software required to run WordPress. The Core Development Team builds WordPress. stylesheets with CSS Custom Properties * [@circlecube](https://profiles.wordpress.org/circlecube/) & [@wazeter](https://profiles.wordpress.org/wazeter/) are close to posting their contributions * [@wazeter](https://profiles.wordpress.org/wazeter/) asked for (and received!) confirmation that contributions should be submitted as PRs to the [`try/custom-properties` branch](https://github.com/ryelle/wordpress-develop/tree/try/custom-properties) of [@ryelle](https://profiles.wordpress.org/ryelle/)’s [WordPress Develop fork](https://github.com/ryelle/wordpress-develop) * [@dryanpress](https://profiles.wordpress.org/dryanpress/) posted a project status update: - [This Google Doc](https://docs.google.com/document/d/1Z0Wo1W0ZQwFJYPcJ8GlsubA9uKhcFdT8ifYnso82z9I/edit) is the working document with all the steps - Work is continuing on (ryelle/wordpress-develop)[https://github.com/ryelle/ wordpress-develop/pull/2] - [Last week’s chat summary here](https://make.wordpress.org/core/2021/08/18/css-chat-summary-12-august-2021/) covers our discussion around `box-shadow`, why we can’t use HSL and that we’ll be continuing discussion on this PR - This project is targeted for experimental release in WordPress 5.9 and then a stable release in 6.0. To make WordPress 5.9, the project probably needs to be merge-ready by end of August * [@robertg](https://profiles.wordpress.org/robertg/) [asked if `rgba` values should be assigned to custom properties](https://wordpress.slack.com/archives/CQ7V4966Q/p1629407464142400?thread_ts=1629407429.141800&cid=CQ7V4966Q). [@dryanpress](https://profiles.wordpress.org/dryanpress/) [linked to the PR which has some discussion on that question](https://github.com/ryelle/wordpress-develop/pull/4), noting that `rgba` values are mostly used in `box-shadow`. We’ll hopefully soon reach a consensus on this point in the discussion * [@ryelle](https://profiles.wordpress.org/ryelle/) asked for input on [this PR about CSS loading & dependencies](https://github.com/ryelle/wordpress-develop/pull/7). [@dryanpress](https://profiles.wordpress.org/dryanpress/) replied with [a link to an issue he experienced](https://github.com/ryelle/wordpress-develop/pull/7#issuecomment-902273234) with a partial colour change on the user profile page, and saved values not updating after reload * [@dryanpress](https://profiles.wordpress.org/dryanpress/) then announced the start of this week’s `` ### Working Time * [@robertg](https://profiles.wordpress.org/robertg/) has taken on `src/wp-admin/ css/customize-controls.css` which 2900+`lines of CSS. Bon courage Robert! * [@wazeter](https://profiles.wordpress.org/wazeter/) has looked at other contributors change files in order to see how others have approached the problem, which seems like a sensible approach ## CSS Link Share / Open Floor * [@dryanpress](https://profiles.wordpress.org/dryanpress/) [shared a tweet about pending browser support for the experimental `accent-color` property](https://twitter.com/Una/status/1427688970289287172) which would set a custom colour to form elements in one simple CSS rule * [@dryanpress](https://profiles.wordpress.org/dryanpress/) also [shared a link about Chromium based browsers soon supporting dynamic CSS module imports in JavaScript](https://web.dev/css-module-scripts/) Thanks everyone! [#core-css](https://make.wordpress.org/core/tag/core-css/), [#summary](https://make.wordpress.org/core/tag/summary/) [ ](https://profiles.wordpress.org/glendaviesnz/) [Glen Davies](https://profiles.wordpress.org/glendaviesnz/) 12:45 am _on_ August 20, 2021 Tags: [5.9 ( 104 )](https://make.wordpress.org/core/tag/5-9/), [core-editor ( 756 )](https://make.wordpress.org/core/tag/core-editor/), [dev-notes ( 647 )](https://make.wordpress.org/core/tag/dev-notes/), [gallery ( 3 )](https://make.wordpress.org/core/tag/gallery/), [gutenberg ( 546 )](https://make.wordpress.org/core/tag/gutenberg/) # 󠀁[Gallery Block Refactor Dev Note](https://make.wordpress.org/core/2021/08/20/gallery-block-refactor-dev-note/)󠁿 ## The problem If you have ever added a custom link to an 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. and then tried to do the same on a Gallery image, you will understand the frustration and confusion of not having consistency between different types of image blocks. This inconsistency is because the coreCore Core is the set of software required to run WordPress. The Core Development Team builds WordPress. Gallery block stores the details of the included images as nested elements within the block content. Therefore, the images within a gallery look and behave different from images within an individual image block. There are some long-standing open issues related to this: * [https://github.com/WordPress/gutenberg/issues/11436](https://github.com/WordPress/gutenberg/issues/11436) * [https://github.com/WordPress/gutenberg/issues/10057](https://github.com/WordPress/gutenberg/issues/10057) The only way to fix this with the Gallery block in its current state is to try and replicate the additional functionality that the Image block has in the Gallery block, and vice versa. While this would be possible, it would lead to an additional maintenance overhead to keep the UIUI User interface and underlying code in sync between the two blocks. ## Changes made To make the behavior of images consistent between the Image Block and Gallery, while avoiding code duplication, the core Gallery block [has been refactored](https://github.com/WordPress/gutenberg/pull/25940) to save the individual images as nested core Image blocks using the standard core` innerBlocks` APIs. To make this work with the `innerBlocks` 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., the gallery structure also had to change from an ordered list to a collection of figure elements within a figure. This structure change also brings the core Gallery block into line with the [W3C WAI guidelines on the grouping of images](https://www.w3.org/WAI/tutorials/images/groups/). The structure change means that Gallery images now have the ability to add custom links, or custom styles, for each image. An example of the flexible Gallery layouts this opens up can be seen below. [[ Gallery images will also automatically inherit new functionality that is added to the Image block, including those added by plugins. Below is an example of a Gallery block making us of the Image wave style and vintage filterFilter Filters are one of the two types of Hooks [https://codex.wordpress.org/Plugin_API/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. option added by the CoBlocks 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/](https://wordpress.org/plugins/) or can be cost-based plugin from a third-party.. [[ Other benefits include being able to use the standard move, drag and drop, copy, duplicate, and remove block functionalities. Keyboard navigation also benefits from the adoption of the standard block model by the Gallery block. ## Accessing the new Gallery Block To access the new Gallery block you will need to download the latest version of the 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/](https://wordpress.org/gutenberg/) plugin. At the time of writing the change is still under an experimental flag, so once the plugin is installed check for an experimental setting ‘Enable the refactored gallery block’ and enable it if it is present: ![](https://lh6.googleusercontent.com/4LymElR1S1bUjhI6slJu4RkZliDBucvmb6muk15r3SUhKnOwmk- _4bT5ile3No1LO61wA1lVkTh002a-ohxEOr0BVI6mnorBA-DuR3CPwIBlU1xUPUWSnHXrgwoTgPss2J- VhA3D=s1600) If this flag is not present it means that the changes have been taken out of the experimental phase. Currently, only new gallery blocks added after the experimental flag is turned on will be in the new format, all existing galleries will be editable and viewable in the current format. You can manually transform an old format gallery to the new format by clicking the ‘Update’ button that will appear in the block toolbar. ## What theme and plugin authors need to do before 5.9 To support the new Gallery block format, plugin and theme authors should aim to do the following before the December release of this change in WordPress 5.9. * Add additional selectors to target the new nested image block in both the editor and front end (existing selectors must remain to support the existing gallery block content). The new structure can be seen below. ```wp-block-code
Image gallery image
Image gallery image
``` Example CSSCSS Cascading Style Sheets. with selectors for old and new gallery formats: ```wp-block-code .wp-block-gallery .blocks-gallery-item img, .wp-block-gallery .wp-block-image img { .wp-block-gallery .blocks-gallery-item figcaption, .wp-block-gallery.has-nested-images .wp-block-image figcaption { ``` **Test block transformations. **Temporary transformation filters have been added to handle the transformation of 3rd party blocks to and from the new core gallery block format. However, block plugins with gallery transforms should still be tested with the Gutenberg plugin to ensure these transformations work correctly. In the future, the temporary transformation filters may be deprecated, and plugin authors will then need to update their transformations to handle the new Gallery format. Notice will be given ahead of this change being made. ## Additional context and considerations ### Other existing solutions Third-party block developers are currently solving some of the problems caused by the limitations of the core Gallery block by implementing their custom Gallery blocks. These include some of the missing functionality, like the ability to add custom links to individual images. This can be problematic for site owners and content editors due to a large number of Gallery blocks that offer very similar functionality, but none of which appear to provide a close match to the functionality available with individual core Image blocks. There do not appear to be any examples of plugins that already solve this problem in a way that utilizes Image blocks as inner blocks. ### Backwards compatibility considerations This is a breaking change due to the fundamental change in the underlying Gallery structure. Due to the large number of Gallery blocks already in use, along with themes and plugins that may rely on the existing structure, the following steps have been taken to mitigate the impact of this change on theme and plugin developers as much as possible: * For the initial release in the Gutenberg plugin, there will be no automatic migrationMigration Moving the code, database and media files for a website site from one server to another. Most typically done when changing hosting companies. of existing gallery content. This means that all existing gallery content will behave the same in the editor and front end as it does now, so will be compatible with existing plugins and themes. Only new gallery blocks added after this change will have the new structure in the editor and the front-end.  The plan is to add automatic migration of existing gallery content when loaded in the editor to the 5.9 WordPress release. * [Two temporary transformation filters](https://github.com/WordPress/gutenberg/pull/33861) have been added that will handle the transformation of 3rd party blocks to and from the new core gallery block format. ### Possible edge cases The refactored Gallery format has been tested against the following sample block libraries that have existing transforms to and from the core Gallery block: * [Jetpack blocks](https://jetpack.com/) * [CoBlocks](https://wordpress.org/plugins/coblocks/) * [Lightbox for the Default Gallery & Image Block](https://wordpress.org/plugins/gallery-block-lightbox/) The following themes have also been tested to make sure that both the existing gallery content and the new format galleries display correctly: * TwentyNineteen * TwentyTwenty * TwentyTwentyOne * Astra * [Arbutus](https://github.com/WordPress/gutenberg/issues/30711#issuecomment-899987854) While the refactored gallery works effectively with these plugins and themes, there may be edge cases in other plugins and themes that have not been accounted for. Themes that heavily modify the gallery CSS based on the existing `