Is Dokuwiki compatible with PHP8? I couldn't find a clear answer for this question on the wiki nor any mentions of PHP8 on the forum in a search.
Nope. Not yet.
See https://github.com/splitbrain/dokuwiki/issues?q=is%3Aissue+is%3Aopen+label%3A%22PHP+8%22 for open issues.
Thanks. I updated the requirements page on the wiki to note this.