The third bug in the recent wave of regressions (T253819 https://phabricator.wikimedia.org/T253819: Dancing Search Bar in MediaWiki) is a high visibility bug, it happens at a range of screen widths on all wikis for any kind of users (readers too). A reddit video of it https://www.reddit.com/r/softwaregore/comments/gtbdwu/cant_fit_all_the_buttons_in_the_frame_wikipedia/ gained 21k upvotes in 2 days.
I think this should be hotfixed as soon as possible: the current behavior damages the image of Wikipedia.
I've submitted the hotfix on Saturday: https://gerrit.wikimedia.org/r/c/mediawiki/skins/Vector/+/600358 Further steps require +2 access. Today there are 2 SWAT windows left, the patch is simple, I hope developers familiar with Vector will take swift action.
Note to reviewer: The patch simply reverts the rename of `emptyPortlet` class in the JS, similar to the hotfix of the 2nd bug which reverted the rename in CSS: https://gerrit.wikimedia.org/r/c/mediawiki/skins/Vector/+/599468
Additional note: the CI test fails with an unrelated 'phan-taint-check-plugin' error detailed in the previous email.
Explanation of the issue: * CSS: `.emptyPortlet` class hides the menu * JS: removes the `.vector-menu-empty` class instead, which does nothing, thus the More menu remains hidden. * The menu collapsing logic's size calculation expects the menu button to be visible. Without that it decides there is enough space to uncollapse the recently collapsed tab, thus the dance begins.
Demian (Aron)