In the mlem community, I clicked on this post:
I was shown the title and post abouta protest taking place at Reddit HQ and in Ireland. You can see in the screenshot, the post doesn't really match the community and you can see it was posted to the Reddit community. The comments were all about the mlem app.
There was another post I saw earlier today about someone being shown another user's page when refreshing. Very interesting.
jerboa also exhibts the same tendency sometimes and does not clear the target layer while composing the new layer. putting it down to growing pains. as more dev hands and eyeballs turn to Lemmy and the various clients, things should improve dramatically. if your post was not re: the actual mlem app, but instead the web instance, then I am not sure... the web user interface should be pretty smooth.
edit: typos
This was via the web interface