I had a refurbished ThinkPad that had memory corruption. I only noticed because Firefox started to crash an unreasonable amount. Ran memcheck through BIOS and sure enough it was bad RAM.
Have we considered that maybe Firefox is the cause of bad memory?
/s
It is.
If a tree falls in the forest with nobody around to hear it, does it make a sound?
If a computer flips bits while it's not doing anything with that memory, does it have bad RAM?
A fair number of people pretty much only use their computers as web browsers.
QED