History will be cleared by Ccleaner and that kind of program. Bookmarks? Well, you have got the HTML or other backup somewhere, haven't you?
My computer life is based on FF Bookmarks - a hundred or so on the toolbar - and I don't like linking this kind of data between devices so just update laptops etc., with a file on a stick.
When Skype goofed up and upset my phone numbers, (only the sub-directories) I realised just how much I relied on modern 'handy' software. Trouble with that one was that the .vcf backup file didn't overcome Skype's bug, so I had to wait for them to fix it - which they did with 7.22.0.104 Phew!