Debugger mochitests currently leak if you run them one by one, or as a set, but not if they run as part of the whole mochitest-other suite. We should fix this. Mihai made the terrific diagnosis that DH_allowConnection holds on to various DOMWindows. I'm testing a patch with more extensive changes right now.

This fixes the leaks, but 2 tests are broken. The bug is probably in the tests and I hope to have it figured out tomorrow.

This version fixes all the leaks. The culprit was the _allowConnection handler as Mihai discovered, so we now make sure to clear it on DebuggerServer.destroy(). After adding a few more cleanups there, it became important to carefully coordinate shutdown and opening in the notification box that appears when the user tries to open another debugger in a second tab (or window). We now wait for the Debugger:Shutdown event before opening the second debugger, so everything works as before. Try: https://tbpl.mozilla.org/?tree=Try&rev=deaca566213b

Comment on attachment 663427 [details] [diff] [review] Patch v2 function run_test() { // Allow incoming connections. - DebuggerServer.init(function () { return true; }); + DebuggerServer.init(function () true); can you get that down to just 3 characters? :) I wish I had something funnier to say here. R+.

Last try push had a couple of oranges in the modified unit test, so I made it more robust. The same issue with restarting the server after it shuts down that I mentioned in comment 2. Try run was clean this time: https://tbpl.mozilla.org/?tree=Try&rev=5c7fe9ff1b99