User blog comment:MisterWoodhouse/The first migrations to the Unified Community Platform/@comment-45204017-20210106112331/@comment-1807002-20210106215137

An example of out of date / no longer supported by MediaWiki Editors (if you scroll to the bottom of that link's page) it shows that the Legacy Source Editor (aka my favourite and preferred editor) has been out of date/no longer supported since 2018. This is just one example of an out of date feature we only have been able to use with duct tape Fandom updates and it cannot be done indefinitely.

Just a reminder, MediaWiki is what Fandom uses— they (Fandom) do not decide what the MediaWiki foundation removes or when they update. Fandom have been for sometime making roundabout ways to keep Legacy running for as long as they have but it is was a matter of time before complete collapse.