When you cleaned does that mean uninstall firefox and deleting Mozilla folder as well?

I'm using the german version of firefox so I'm not sure if my translations are fitting totally to the items shown in the english one. No, I didn't deinstall firefox nor delete the folder. I chose "informations to solve problems" from the help menu, where all settings are shown. On the upper, right side there's a button to clean up firefox, that's what I did. I hope someone can understand my description.

hi, netflix depends on IndexedDB, a storage technology, that isn't available in private browsing mode - setting firefox to keep no history effectively makes your browser run in permanent private browsing mode. until mozilla dedicates some resources to change this behaviour in https://bugzilla.mozilla.org/show_bug.cgi?id=781982 there isn't really a way around that unfortunately. perhaps you can set some custom history settings though that get close to what you want to achieve without sacrificing to be able to play content on netflix...

Sear Philipp, many thanks for the fast and competent answer. If this is the reason there'll be no "simple" workaround, I agree. So I'm a little bit disappointed because there's no comfortable solution but also satisfied to understand a little bit more of the background for this dilemma. Kind regards, Joerg