Librewolf is definitely better if you are a hardcore privacy nerd. I used it but it broke some sites due to the privacy settings. Waterfox is better than Firefox privacy-wise. Waterfox is in the sweet spot for me. Waterfox has an app but I do not like it because it was very slow compared to the Firefox app. I use Waterfox as desktop browser and Firefox as mobile browser.

Here is the link without the need to open reddit. https://www.waterfox.net/blog/a-new-chapter-for-waterfox/

There are several Firefox forks. Waterfox (based in Europe UK), Librewolf, Zen etc.

Unfortunately, this map isn’t accurate anymore. For example it says that Startpage only uses Google search results but that’s outdated. Now Startpage uses Bing and Google search results. https://www.startpage.com/privacy-please/startpage-articles/enhanced-search-results-on-startpage ‘In working with Microsoft, Startpage is now incorporating Microsoft Bing search results and ads within some results pages, using a custom-built private search solution. Google search results will continue to broadly be used, but incorporating additional high-quality sources will have ongoing returns for our users’