For me, the autoscroll icon is only invisible on Ubuntu 20.04 Wayland, but visible on my Debian Testing Macbook (Gnome Wayland, Plasma Wayland) - as long as I don't run into the crash.
Bug 1638084 Comment 8 Edit History
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Offtopic, as it affects "last good" as well: For me, the autoscroll icon is only invisible on Ubuntu 20.04 Wayland, but visible on my Debian Testing Macbook (Gnome Wayland, Plasma Wayland) - as long as I don't run into the crash.