“As perfluorinated compounds (PFCs), all Fluorinert variants have an extremely high Global Warming Potential (GWP),[1] so should be used with caution”

That page also says

“Although Fluorinert was intended to be inert, the Lawrence Livermore National Laboratory discovered that the liquid cooling system of their Cray-2 supercomputers decomposed during extended service, producing some highly toxic perfluoroisobutene. Catalytic scrubbers were installed to remove this contaminant.”

Perfluoroisobutene is a schedule 2 substance, in the sense of the Chemical Weapons Convention (https://en.wikipedia.org/wiki/List_of_Schedule_2_substances_...), so it’s a substance that “can either be used as chemical weapons themselves or used in the manufacture of chemical weapons but that have small-scale applications outside of chemical warfare and so can be legitimately manufactured in small quantities”.