This button has been missing since the version 115.2.1.
I am requesting this button to be added back as it saves a lot of time. Now instead I have to share it to the other app (download manager in this case).
Before I could just tap and hold a .mp4 video and select "Open link in external app" and at first it used to ask which app to open .mp4 files with, and from next time Firefox just remembers it.
Its just so annoying, I wish this button was not removed in the first place. Also long-tapping some videos and images do not open the context menu at all. have tried it in multiple versions of Firefox Android across the same site and image.
All the versions after 115.2.1, even the lastest version 134.0.2 lack this button.
Please add it again!!