I digged one out of the junk bin at work (where all our ST boards live). It was marked as MB915-B00. It didn't power up so I couldn't conduct a live saw experiment. But from a quick inspection, there doesn't seem to be an official "cut here" line between the display and the programmer. There is a little bit of space, but it is used, for example, by a horizontal traces.
Anyway, STs eval licene is rather restrictive when it comes to using the eval board in some producr setup. Read it for a good laugh end hen move on to another manufacturer.
By the way, there is an attempt at an open source compiler for the 7 and 8 ST MCUs. When we looked at it, it was unusable. And as we have learned, ST won't give open source compiler developers a helping hand. Despising open source and thinking throwing cheap eval boards at the masses is enough to win the hearts and minds over.