Today WordPress 5.5.3 was released, the day following WordPress 5.5.2.
It is suboptimal to have releases this quickly in succession, but the details below hopefully describe a scenario that you will agree was worth resolving as quickly and safely as possible.
5.5.2 and ZIP installs
An error with one of the fixes made in WordPress 5.5.2 caused an issue with installing ZIP packages available on WordPress.org The community site where WordPress code is created and shared by the users. This is where you can download the source code for WordPress core, plugins and themes as well as the central location for community conversations and organization. https://wordpress.org/ for new versions of 5.5.x, 5.4.x, 5.3.x, 5.2.x, and 5.1.x. The issue only affected fresh WordPress installations without an existing wp-config.php file in place.
During the release process for 5.5.2, the package testing workflow returned a false positive, so this issue was not caught. This is a difficult issue to test for, but the first steps are to update the existing documentation so future release teams can learn from this experience. Additional research will be required to find a long-term solution. Updates on this progress will be shared in future Make/Core Core is the set of software required to run WordPress. The Core Development Team builds WordPress. posts.
To fix this issue, the Core team released WordPress 5.5.3. It provides a clean ZIP package for the WordPress.org download page for the 5.5.x, 5.4.x, 5.3.x, 5.2.x, and 5.1.x versions.
Resolution of 5.5.3-alpha
While work was being done to prepare for WordPress 5.5.3, the release team attempted to make 5.5.2 unavailable for download on WordPress.org to limit the spread of the issue noted in the section above, as the error only affected fresh installations. This action resulted in some installations being updated to a pre-release “5.5.3-alpha” version (see more here). The appearance of a 5.5.3-alpha version is now resolved with the help of the Systems team.
WordPress 5.5.3-alpha has no functional differences to the 5.5.2 release. To correct this version on your site, you can either click the “re-install WordPress” button on the
Dashboard → Updates screen or update to 5.5.3.
Props to @jeffpaul for drafting this post, and to @chanthaboune, @cbringmann, @audrasjb, @davidbaumwald, and @hellofromtonya for editing.