Depending on the region where they were sold, Samsung Galaxy S20 could use either Snapdragon 865 or Exynos 990 CPUs.
The Mozilla messages fail to mention this information that is essential for any CPU bug, which CPU model was used in the phones with crashes.
It is more likely that the bug is present in the Samsung Exynos 990 CPUs and not in Snapdragon, because Cortex-A77 was used much more widely, so it is improbable for such a bug to not also be noticed elsewhere.
The standard S20 used Snapdragon in North America, and Exynos in Europe.
For the S20FE the Snapdragon version was sold in Europe - which was a selling point by itself.
I did not know that the S20FE had Exynos at all until I just looked it up...
Apparently version 1 does, while version 2 uses Snapdragon.
The Mozilla messages fail to mention this information that is essential for any CPU bug, which CPU model was used in the phones with crashes.
It is more likely that the bug is present in the Samsung Exynos 990 CPUs and not in Snapdragon, because Cortex-A77 was used much more widely, so it is improbable for such a bug to not also be noticed elsewhere.