Sometimes when I return to my computer after using Thunderbird, but having left Thunderbird open, a message appears at the bottom asking me if I want to undo "ignore thread" for some message or other. The problem is that I didn't intentionally tell Thunderbird to ignore a thread; I don't even use the feature, ever. However Thunderbird ignores threads anyway. I completely lost track of several important messages before figuring out that this feature (which previously I wasn't even aware of) seemed to be activating spontaneously. Am I doing something that could trigger it? This only happens if I leave Thunderbird open while I'm away from the computer. On my return, I find the message asking if I want to undo "ignore thread." I think the thread in question may be one that's highlighted because I have left the cursor resting on it. But surely that shouldn't be enough to make Thunderbird ignore the thread. Or is it? It's been happening a lot lately.