Each time i open FireFox, it opens as it was just installed/updated. All opened before tabs opening as they should, but all data (options/preferenses) in addons is not saved. Usually, when i was closing FF, all tabs, options, addon's options were saved, and after next launch they were restored (so if i marked in one of the addons "do not open this page when the info could not be found" the page is not opened). This is not addon bug, because the data is not saved in ALL addons. And that appeared after automatic FF update (FF did not give me the opportunity to have the previous version of the brouser without updating)

From 23-th of Ferbuary untill 1-st (or 2-nd) of April i had a conversation with Skype Tech Support, and the problem was that the last version of the programm was not suppored by my OS version