UMLR — issue within UPDM with profile diagrams

there is an issue within UPDM with profile diagrams. As there are multiple stereotypes in the diagrams, showing metaclass and extension clutters the diagrams.
They become literally unreadable in the spec as they need to fit in the page, since every element takes addition space for extension:

In MagicDraw, we have such notation:

It saves time, is intuitive, but this is non standard thing, so we cannot use it in UPDM.

I would like to raise an issue on the notation of extended metaclass, but I'm open for discussion