Master M in script editor of lc8.15

[james at thehales.id.au]

Has anyone noticed the "Master M" (where the M is actually a blue tiled M) in the top area of the script editor in LC8.15?
I have checked both the commercial and business editions and both show it.
It is not present in LC8.14 or lower.
It doesn't do anything, just sits there.

Perhaps an upcoming feature or perhaps a slip.

Intrigued.

James