I somehow can't respond to remote comments

Now, 2 posts in a row i see that I can't reply to comments on remote communities.

One was to lemmy.world, and the other one was to programming.dev.

My network tab doesn't show any activity after submitting the comment. Just the spinny SVG icon. So far, I have tried with 2 different browsers.

I tried posting to !mlemapp@lemmy.ml from mlem on my phone, and that worked without issue. So, now I don't know if it's the instances I'm trying to post to, or the web app, or...