Moving on from Firefox (kicking and screaming)

After Firefox and Waterfox failed to properly display two websites this weekend, in one case making the site unusable for what I wanted to do, it seems clear the end is near for using Firefox as a default browser. Compatibility….bah. I have used Firefox and its forks for close to 20 years. Most of that time it has been my favorite browser. It is still my favorite when it works. I cling to it stubbornly since I don’t like that chromium-based browsers have taken over completely, but also because it is more customizable and works better….when it works. (The separate search and address bars is a big plus, as someone noted on these forums not long ago.) But the time is coming to switch to a chromium-based browser for daily use. Sad, but true. Any Firefox fans who have made this switch have advice? Pretty sure I will switch to Brave and use Firefox as backup—flip-flop of what I do now—keep Waterfox as second backup and also Edge on my Windows PCs. Hoping someone shares the secret of making Firefox compatible with all web pages, so we can continue to enjoy it.