i use revolution (selamectin) from the vet and it’s like a fucking flea nuke. if you’re getting it soon i wouldn’t worry about fleas getting in the house because once you use this stuff it’ll clear all of them out of the area in literally hours. fantastic stuff.
also, don’t trust any over the counter flea sprays or treatments at stores, they all use neurotoxins that they claim is safe for cats, but some cats are more sensitive and it might cause neurological damage or even death.
linux typically won’t hard freeze on errors like that no matter the distro. it can, but rarely. being an all amd build i suspect there’s some cpu bios feature auto scaling core clock or voltage and in my experience ryzen cpus need to have a manually set stable clock and voltage to perform properly no matter the os. try checking your bios and disabling any powersaving or auto-scaling features for your cpu and manually set it for stock clock and voltage. you may need to look up what these values are as the bios might not have a default value for you. this might not be your issue but it’s worth trying. good luck!