So pretty much, I'm using the latest version, 1.10.0. I'm unsure if this was broken before I updated as I'm just now really testing everything to ensure it works.
The problem is I have two selected topics, I click the merge button, and I just get brought to this popup (that seems out of place as well):
So one, it's not registering that I've selected topics to merge, & two, the popup itself looks like it shouldn't be there. I'm unsure if that's because it's broke or if that's just how it is.