Support link
Fragment of a discussion from Support/LiquidThreads
It points to the bug report form. Please click the sunflower. For Intuition and Wikimedia we moved the reporting there as they rarely respond here.
But why with same method, I can only see an empty box, and it's no way to close, only see a triangle which can't click (See screenshot)?
That's unrelated, it's an issue of FOUC and ResourceLoader which haunts recent versions of MediaWiki core. See for instance phabricator:T112047.