I see a few other posts when I google search for this, but when I want to reply on a post, it takes me to the index of this forum, so hence an additional post about this.
I get "ERROR: Sorry, this request is taking longer than normal." when updating an entry in my LastPass vault.
I sometimes also get other issues, such as the icon does not work - clicking it does nothing, or the auto fill is empty, even though the entry exists, and I am logged in, which also brings me to another issue: sometimes when logging in, I get tht my login failed, but then I am able to access my vault, so the login actually worked, but the error message says it did not.
I use Firefox Quantum 184.108.40.206, on Windows 10, but the problems were present on older versions of Firefox as well.