Try here https://wiki.gentoo.org/wiki/FFmpeg
Created attachment 866978 [details] Screenshot of the error See attached screenshot for the error.
Workaround is to fall back to source-based editing for this page at the moment.
This issue seems to be present when trying to edit most/any pages with the visual editor for many/all users (as brought up in #gentoo-wiki, and I just tried the visual-editor myself and the error in the title of this bug pops up in a "dialogue" during visual-editor "startup"). I think this bug should perhaps be assigned to infra so I'll do that now, sorry in advance if this is wrong. Also this is a bit of a serious issue for the wiki, as it is stopping some users from contributing, so I'll bump up the "importance" of the bug a bit. Thanks everyone.
Maybe it's possible to simply disable the VisualEditor extension if it doesn't work? I personally wouldn't miss it since I never wanted to use it anyway -- occasionally I would accidentally click on the wrong edit button though. :D
i imagine many do benefit from it though, and editing wikis is supposed to be as easy as possible
This issue should be fixed on the next MediaWiki software update (v1.39) and is a problem with the Visual Editor itself. The Visual Editor actually works correctly when creating new pages, but not when editing existing pages. There's a very long discussion about it here: https://phabricator.wikimedia.org/T270377
