While waiting for a new version of Tails with TB 12.5.4+ (fx 102.15.1+), I guess image.webp.enabled = false in about:config is a reasonable workaround (of course you’ll have to toggle this boolean each time, as Tails is amnesic). Thoughts? Any negative side effects?
How about writing about the current situation and this (or a better, if any) workaround on the home mage the opens when you start TB on Tails?
Just a thought. Forgive me, if this is not the right place to talk about this. Thank you very much.