How to continue to use it?
Topic on Talk:Contributors/Projects/Removal of the 2006 wikitext editor
See the information on https://www.mediawiki.org/wiki/Contributors/Projects/Removal_of_the_2006_wikitext_editor
I see only that there could be alternatives, but there are no yet?
Someone has to write one and maintain it...
It was working good and now it should be again written... What a <s>re</s>progress!