In Wikisource, the edit field of proofreading pages is broken. Now it is replaced by the div 'CodeMirrow', and 'div.prp-page-edit-body textarea' is disabled by `display: none`.
This screenshot of a [[ https://ru.wikisource.org/w/index.php?title=%D0%A1%D1%82%D1%80%D0%B0%D0%BD%D0%B8%D1%86%D0%B0:%D0%9F%D0%BB%D0%B0%D1%82%D0%BE%D0%BD%D0%BE%D0%B2%D1%8B_%D1%80%D0%B0%D0%B7%D0%B3%D0%BE%D0%B2%D0%BE%D1%80%D1%8B_%D0%BE_%D0%B7%D0%B0%D0%BA%D0%BE%D0%BD%D0%B0%D1%85_(%D0%9F%D0%BB%D0%B0%D1%82%D0%BE%D0%BD,_%D0%9E%D0%B1%D0%BE%D0%BB%D0%B5%D0%BD%D1%81%D0%BA%D0%B8%D0%B9).pdf/144&action=edit | page ]].
{F25717921}
In Main namespace the editor is broken too.
'CodeMirror' conflict with other gadgets of syntax highlighting (from user settings), so the edit page loading very long or freezes. And the browser tab overload 100% of CPU and make leaking memory.
If disable such gadgets, then anyway have problems in edit. Such as, all edit text shows as underlined and strange colored.