I did a bunch of research on this before leaving my last job, as we were in the same lousy spot. The top 3 contenders at the time were Xwiki (https://www.xwiki.

I did a bunch of research on this before leaving my last job, as we were in the same lousy spot. The top 3 contenders at the time were Xwiki (https://www.xwiki.org https://www.xwiki.org), Bookstack (https://www.bookstackapp.com/ https://www.bookstackapp.com/), and BlueSpice (https://bluespice.com/ https://bluespice.com/) based on Mediawiki. None of them, however, quite fit with our use cases. We needed something that non-tech people could equally contribute to and maintain (so git with static pages was out, as were the many wikis that required writing content in Markdown without a WYSIWYG UI). We needed something with tight integration with Jira, as we frequently used the ability to display Jira issue reports and auto-create wiki pages. And we preferred something that could at least display Office-doc and PDF content transparently, although that was looser. I’m glad I never had to make that call, because killing our self-hosted Confluence was going to suck badly. I’ll never not be upset with Atlassian over that mess. I get why they did it and even kind of understand doing it, but the whole thing was handled in the most user-unfriendly, tone-deaf way possible. And then to have their godawful cloud Jira meltdown happen shortly afterwards and have them not adjust any license terms in apology for it was the topper on the cake.