Mouse input randomly stops working, hc character dead after last occurrence

This has happened a few times in the past week or two across multiple characters. Before then this has never happened. No hardware changes on my end.

Without any apparent reason, I'm suddenly unable to move around by left clicking. Potions and ability hotkeys still work so until this most recent occurrence I was able to frantically mash potions and alt-f4 to save myself. It's not like the mouse itself stops working. The cursor still moves, but clicking does nothing. This doesn't occur in any other game or context.

Just now I logged back in to find my previous hc prophecy character stuck in standard. The really weird thing is that when I alt-f4ed I wasn't particularly surrounded and had way more hp than I've had in hundreds of other logouts/alt-f4s. Still came back dead.

Anyway, that's a ton of time and currency gone due to some random bug. Think I'm done with this game for quite a while.