I had noticed an issue of pages failing to load sometimes while others extremely slow load after either latest version or one before it. Seems this just happens when uBlock Origin is activated.
The stripped down Facebook one I think is
Sorry this somehow gave me a 504 server error yet posted anyway so I wound up with a duplicate. i closed the other.
This is obviously not likely unless Firefox itself becomes reproducible.
I have not had this issue before. All the sites you listed work fine for me. Did you restart your phone to check it just is not struggling to load the characters in the system from a glitch?
If it is actually loading from the site that would expose what your bookmarks are and potentially who you are if that is not exposed by other means, due to it consistently loading same sites same...
GPS doesn't work well indoors but airports tend to be full of large windows so it should be fine.
What is your setting for "show on the lock screen"? Is it on or off? If it is on does turning it off make it not run into same issue anymore?