Bizi, as far as your passwords are concerned I make sure that "Remember Me" or equivalent is enabled on all sites which need a password to be a full member of.

For example, this morning I cleaned up all of my temporary files, including my browser cache. I use CCleaner (https://www.piriform.com/ccleaner/download) for this.

It was then just a matter of a few minutes going through all of my password-sensitive sites. Eg, on NT all that I had to do was to enter "kiwi33" as my screen-name - because "Remember Me" is enabled NT "knows" my password so (obviously) all is good here.

I am not a very active FB user (I am a member of a couple of closed (invitation only) forums) but I have never had a problem seeing them after I have run CCleaner.