In my drag code, i have dragOver be a capturer and dragExit be a bubbler. When these events are registered with AddEventListener, however, the event listener manager notices they are the implemented by the same listener and "or's" the flags together. Now, however, both capturer and bubbler bits are set so the listener will be triggered both on the way down and the way back up. From nsEventListenerManager::AddEventListener for (int i=0; i<(*listeners)->Count(); i++) { ls = (nsListenerStruct*)(*listeners)->ElementAt(i); if (ls->mListener == aListener) { ls->mFlags |= aFlags; //****** NOT GOOD =( ls->mSubType |= aSubType; found = PR_TRUE; break; } Basically, the listener manager is incorrectly optimizing to save space. When flags are different, it should not re-use the same event listener.

Yeah, unfortunately I knew about this one too, but no one had run into it until lucky you.

Moving M16. Mixing the two is rarer than using either alone. Not required for beta.

Unacceptable. I'm taking this bug then.

Punting back to joki, since he says he's close to fixing this.

should work okay now.

Marking verified last comments.