I tend to not update most of my phone's apps. Actually I never do. Well, except ebanking, Signal, and of course, Firefox. I tend to do some of my reading on my phone. And when it involves Firefox I use the Reader View. For the past couple of months the for the vast majority of webpages I am getting a "Cannot Complete Request" message which is super annoying. This is not a webpage issue, but an Android-Firefox issue, as the pages display just fine on my FF on Win10.
There is already a bug (https://bugzilla.mozilla.org/show_bug.cgi?id=1863662) and I just wanted to perhaps make some noise so that is fixed and/or the change that caused it to be rolled back. :)