Apologies for the late response!
I’ll echo similar thoughts to what I said in another comment. Librewolf, Mullvad, and other privacy based browsers are going to be a double-edged sword. You can take me with a grain of salt but these types of browsers actually do make you stand out in terms of fingerprinting. They have their own unique signatures, and the more you tweak the more you stand out too. Does it protect your privacy? It’s really hard to tell, there’s no data to suggest one way or another that I’m aware of. But, these changes are going to make you more likely to be challenged by captcha and blocked by sites in general.
I wish we didn’t have to try and solve this type of problem. Privacy should be a right.
Late reply here too. I’m sorry about that.
You can read my comment that I made here in regards to what I think could be causing you problems.
I do take this seriously and will try to find some time to put together a configuration like this for testing, so thanks for sharing.