Just rebooted and I’m up and running with Fedora Silverblue 40.
(Just tried reinstalling mozilla-openh264 – so videos work in Firefox – but it failed with the same error. Not a big deal, I’m using @Vivaldi as my main browser these days anyway and I guess the Fedora folks will fix this in time.)
More importantly, I wonder if the screen reader has been fixed yet. (Yes, Fedora ships with a broken screen reader.)
onepict