Meanwhile, as the "partial fix" is deployed, here is what I think fixed the issue for me: in the Preferences, under "Privacy & Security", check "Allow Firefox t

Meanwhile, as the "partial fix" is deployed, here is what I think fixed the issue for me: in the Preferences, under "Privacy & Security", check "Allow Firefox to install and run studies" (then wait for the current hotfixes to appear in about:studies then restart the browser).