Sidewise forgetting tabs and resetting settings.

No idea why, but Sidewise has forgotten my hibernated tabs more than once over the past few weeks. I just launched Chrome to find that as well as losing my hibernated tabs, the settings have reset, and sidewise is docked as it would be on a fresh install. None of my other extensions have been reset. How has this happened? If I can't trust Sidewise to remember my (many) hibernated tabs I may as well remove it and save me some RAM...