SkipperWannabe

If you are trying to switch from Chrome, then just use regular Firefox with the ublock extension (and maybe some of the other privacy extension officially supported). If you are a "power user" and want modify/access about:config and other settings then you need Firefox Nightly. The Fennec and Fenix (iirc) are just stripped down Firefox that either only have private mode or additional settings for privacy (that are already present in regular version, but way not be enabled by default). Hope that helps.

There is also this official extension. IIRC, this also makes sure that all the meta owned sites are not able to interact with other sites, but can work fine with each other. It also makes sure that any links leading to their sites also only open in the container, maybe also sanitized to remove the tracker from original link. The last part I am not sure, as I might be confusing it with a different extension. But if you are using any of the Meta sites, I would recommend it.