Waterfox is also a good replacement for Firefox or Cachy Browser.
As a plus when compared to Librewolf, they also have an android app available and fully support Mozilla sync between the two.
It was a bit buggy and was not integrating with FDM etc.. Good decision. Hardened Firefox is fine.
I was stranged yesterday when I updated my CachyOS in a VM, and saw 137.x.x in Cachy Browser, being Firefox 139 since a few days.
To be honest, I used a few times, cause it came preinstalled, but I’ve been using Zen Browser for a few weeks now and it’s pretty promising, plus, my main web browser since about a year or so is the already mentioned by @Sunda-Spirit, FireDragon, by the Garuda Linux team, the only thing I don’t like at all, is that they moved from Librewolf base to Floorp, so it’s Firefox ESR, but well, soon Firefox 140 will come out and I hope they’ll update the base soon 
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Rest in peace, Cachy Browser 
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cachy browser works perfect and fast still please people should update and improve it all time 
Cachy browser is discontinued since a while.