User blog comment:MisterWoodhouse/Blogs are now available on the Unified Community Platform/@comment-43528456-20200816191045/@comment-26339491-20200820230527

No to the first question - Discussions and comments are built on a completely different technology from MediaWiki, and so wikitext doesn't work there.

We're not aware of a systemic issue with session errors, but if you keep seeing them for no good reason, I'd send a bug report via Special:Contact so we can look into it!