Orion is a macOS browser. macOS already has pretty decent screen capture. Cmd-Shift-4 immediately brings up a selection box for a screenshot, while Cmd-Shift-5 has additional options including screen recording.
Besides that, a browser should by concerned with web browsing, while an OS or a third-party application can dedicate itself to screen capture.
I don't understand why Firefox has spent resources on a screen capture utility when all operating systems provide it. Seems like an excessively broad feature.