There's a bug I've been running into lately (last week or two but today was first time it's appeared multiple times in quick succession) when trying to post/queue something to a topic. The operation spins for a minute or so and then errors out and most of the window is filled with a brown error dialog which contains loads of error messages concatenated together going on for 20-30 lines. It quickly disappears before I can take a screen shot.

For a specific case, it happened multiple times this morning before/after 8:05am PDT on the topic teabagging.

Additionally, I got a new error screen when I go back and try to reload that topic after the posting errored out (posted below). It continues to throw that error page until I seem to be able to reset things by opening a completely different topic. I was able to reproduce this more than once (the failed posting and then getting the error screen). In one case, what I'd posted later showed up in the topic; in the other case(s), content never appeared. The posting that was double posted is the latest image in the topic at present. I went and deleted the duplicate.
Photo by wolfgang678 with the username @wolfgang678,  April 22, 2019 at 6:06 PM. The post is about the topic Sharesome Support and the text says 'There's a bug I've been running into lately (last week or two but today was first time it's appeared multiple times in quick succession) when trying to post/queue something to a topic. The operation spins for a minute or so and then errors out and most of..'