No problem :)
There’s a FOSS fork of Signal which removes Google dependencies from the software.
Signal-FOSS
A fork of Signal for Android with proprietary Google binary blobs removed. Uses OpenStreetMap for maps and a websocket server connection, instead of Google Maps and Firebase Cloud Messaging.
From a post on the GrapheneOS forum:
If you try to “update” it from aurora store, the update will fail because the signature does not match between the open source version you have installed as part of the system image, and the google version on store.
Its nothing to worry about, just ignore it.
Just add it to Aurora Store blacklist.
I don’t think it’s browser specific or a direct targeting of Firefox; that’s likely confirmation bias. I see rolling captchas and the annoying ones that have a delayed fading in and out even on Chromium forks. I think the biggest reason for seeing them is VPN usage. When I turn off my VPN, I either don’t see any captchas or it just automatically shows the green check when I start them.