Its doing the same thing too me, I have noticed that everytime I leave Timo that it clear out ALL my cookies for any site that I have cookies saved by default.
Getting to be a pain in the arse. Cuz not only do I have to relog into Timo but I must at XPC as well.
Something has been done that it clears the cookies upon leaving the timo pages. I noticed it started just after some database changes were made to make caching faster or something like that. It started happening just after that.