The "Restore Defaults" doesn't restore the Security Level preferences
While reviewing !464 (merged), I've noticed that the "Restore Defaults" link in about:preferences#privacy doesn't do anything (see also !464 (comment 2860237)).
Initially, I thought adding an is="text-link"
was enough, because some telemetry nonsense looks for that attribute, which we're missing and we get an exception that is visible in the console.
However, adding it doesn't seem to be enough, and we might need some additional investigation.
As a workaround, the button in the panel works, so we might release 12.0 with this problem, and add it to known bugs.
/cc @richard @duncan