In Thunderbird, I am no longer able to drag a message to a different folder. It stopped working after a live upgrade from 11.3 to 11.4.

The behavior is that I click on a message and start to drag it. The cursor turns into the hand holding a message. Previously, if I dragged it over another folder, the folder would underline (I believe... since it was working, I paid no real attention, and I may be misremembering how the folder display changed) so I'd know that releasing it would place it there. Now, the folders never change, the cursor stays unchanged, and releasing the mouse button does nothing.

I can of course move a message using the menu option (Move To), but that's not nearly as convenient.

I've tried both version 3.1.7 (from openSuSE updates repository) and 3.1.8 (from the build.opensuse repository), and neither correct the problem. I'm not sure what version I was running prior to the live upgrade, but it was whatever was most recent in the build.opensuse repository. My guess is it's a problem related to one of the widget toolkits somewhere (perhaps some config thing on my part that didn't make the transition correctly) but I don't know how to determine which one, or how to correct it.

Any suggestions short of a complete rebuild?