Firefox update breaks media autoplay setting

In Devuan Daedalus, updating from firefox-esr 128.3.0esr-1~deb12u1
to 128.3.1esr-1~deb12u1 appears to have broken the media autoplay
setting, as measured by YouTube ads playing immediately after page
load, even though media autoplay is turned off (except for a couple
of about:welcome* "sites".

In an attempt to workaround the apparent (and possibly deliberate)
bug and following this page

    https://connect.mozilla.org/t5/discussions/firefox-dont-block-video-play-even-if-autoplay-is-prohibited/m-p/49998

I have these settings in about:config:

dom.media.autoplay-policy-detection.enabled true
media.autoplay.allow-extension-background-pages false
media.autoplay.block-event.enabled false
media.autoplay.blocking_policy 1
media.autoplay.default 5
media.autoplay.enabled false
services.sync.prefs.sync.media.autoplay.default false

Even with that, YouTube ads play without warning.

Are there any known workarounds (other than switching to another
browser?)

Thanks.

--
Robert Riches
spamtrap42@jacob21819.net
(Yes, that is one of my email addresses.)