Giving this a 3 star because its a great product, however their latest update really botched everything. For people looking for a permanent solution unlike the disabling it and re-enabling it (only works until you restart Firefox), you can first back up your tabs using the methods many other reviews have outlined, then scroll down the OneTab page to the More Information section. Here you can click on the link to previous releases, uninstall OneTab and then install version 1.29 and restart Firefox. You may also want to disable automatic updates in the extension settings so it doesn't update again, and this WILL clear any tabs you have loaded in it, so remember to back up the folder before restoring it afterwards. Hope this helps and doesn't get buried instantly.