Recently I have experienced extremely slow loading times for some web pages in Firefox, e.g. on Flickr. In some cases they fail to load even after a very long time. Whenever this occurs, I paste the same URL into Chrome and that browser loads the page instantaneously.
Both browsers are running uBlock Origin and Malwarebytes Browser Guard. I’m also using Dark Reader on Firefox, but turning that off doesn’t improve loading times. Any advice would be gratefully received.