Did they mention external device access? I only see a mention of portable LibreWolf which I assume is referring to the “can just be ran from a folder dropped anywhere on the filesystem” version of portable, not necessarily that it’s an external device.
My company enforces specific add-ons for Firefox so I installed and use LibreWolf which our admins don’t lock down - only Chrome and Firefox. I wanted a browser that I would use separately from my work that didn’t specifically need their add-ons which include traffic sniffing crap. I know that if I want to do any personal browsing and guarantee it’s personal, I should use my own device but I was honestly just annoyed by the additional CPU cycles the security add-ons were using.