I doubt you can force them to provide the service with the original terms, but you might be able to ask for a (partial) refund. If not today, after a week of verbal abuse they will receive for this online.
As I understand it this bypasses a "please do not read" level of protection on cheap microcontrollers, not an actual secure element, so only those secrets are impacted that were not properly protected to begin with.
Firefox on Fedora 43 here, no joy, and indeed, randomly broken on Linux (too).
[edit] Okey, so installing the complete Google Noto Fonts family resolved this issue. But I still don't know if relying on a script with almost no font support is any better than what the OP did.