Crashes Firefox at startup Rated 1 out of 5 stars

I've always been very happy with this add-on but since the newest update 2201 / 2301 the add-on is making Firefox crash at startup. I already tried deactivating all other add-ons, so it has to be Tree Style Tab's fault. Please fix this!

This review is for a previous version of the add-on (0.14.2013082201.1-signed).