I'm having trouble finding an example of the thumbnail issue again right now but I was seeing the pictrs conversion parameters passed to URLs from catbox.moe, i.postimg.cc, and other sources in the CSS for the thumbnail when I reported the issue to Tiff ~3 weeks ago. It's possible that it got fixed/suppressed by another change since then though. (0.0.44 was deployed a few hours ago and I think there may have also been a beta patch bump for the lemmy backend at some point since I reported the issue originally in our local support community.)

I'll let you know if I see it pop up again.

For the text handling issue, I was seeing text like " by in " (i.e. "<thread title> by <username> in <community>" if it still happens) getting misinterpreted as raw HTML instead of being escaped. (i.e. <!-- raw HTML omitted --> was showing up in the HTML output for the page.)

You may recognize that text as the pattern for a recently fixed bug in the user profiles; I found the text handling issue while trying to explain the other issue to Tiff a few weeks ago.

Will edit this comment immediately after posting to let you know if I still see the text issue.

EDIT: I still see the text issue show up in this comment. https://old.reddthat.com/comment/10370610