Thought I’d share what I’ve found.

1. When posting comments - If you see the eterntal spinning, try changing the language (eg to english). I discovered this as when I tried posting to the same post on Jerboa (android) and it gave an error about that language not being supported (no languae was chosen). I changed my default language to “undetermined” and that didn’t work, changed it to “english” and still had the spinning circle.

What works is not having a default language and then choosing one for that comment.

eg here https://lemmy.world/post/272773?scrollToComments=true

2. When creating a community - if you see the spinning circle, it is likely that the community is already created, though no error message is shown. When searching for the communty, the description is shown, not the lemmy name eg. when searching for nde, you will find “Near Death Experiences” but not nde or !nde so you may miss it and try to create it.