Today lightning started to hang up thunderbird shortly after startup with 100% cpu, no I/O and constant memory usage. I verified the cause by deactivating it. Since this also happens with a completely different installation and a different server-side account, I suspect the server (owncloud) sends something awkward. I read about debugging a thunderbird extensions using the firefox tools, but I cannot connect the debugger, since the main drawing thread is blocked (and thus the connection cannot be accepted). The error console seems to be empty.
Is there any other known strategy to debug a running thunderbird/lightning app? Can I dump the js state? Log all lightning actions to the console? Any other idea to pinpoint the culprit?