That’s when I realised that the word ‘REAR’ was lit and therefore this must be a clickable button. Indeed it was.
The two icons above the control dial turned out to also be buttons you can press.
This is terrible user interface design. There was nothing on the word ‘REAR’ to indicate that it was clickable. No depression to feel, no underlining or other symbol that might indicate that you could click it.
Also, it doesn’t really depress when you press it, so it doesn’t have the feel of a control you could click.
Wonder what the folks at @atpfm would make of this?