I suspect that either Google has opted to block this in Firefox for Android, or it is somehow a security feature. I can't understand it, though. Scrolling screenshots can be performed in other apps.
I was able to do this on my Samsung flip 3 but now that I switched to a new Google Pixel it's not available for firefox. I'd rather not have to use Chrome in certain situations just to have this feature.
I have been using OnePlus 8t for 4 (after 10/2020) years and this feature has been working on their OxygenOS from the beginning and it is still working.
A couple of days ago I changed my daily driver to Google Pixel 9 Pro with Android 15 and now the rolling screenshot feature is no longer available with Firefox. I can use it with Chrome and with many more apps though.
When will this core feature be fixed? I am very disappointed that the feature is not working even many people have been complaining about the situation for years.
This is almost the last straw for me. Chrome works better in almost every way regarding auto fill and other things like this that make the experience using the app pleasant