Is your feature request related to a problem?

When creating documentation based on models, it is nice to be able to quickly select the section of a model needed, and paste it in.

Describe the solution you'd like

When using Edit > copy, in addition to the gaphor format blob, plain text, vector and bitmap elements are written to the clipboard, to be accessible to other programs - wordprocessors, presentations, etc.
The text should be some human readable version of the elements and their attributes, with edges at the end. Ideally, the format is also moderately easily machine parsable. Possibly PlantUML may be a good target, even if it is not fully implemented for this. This may be related to this issue about textual descriptions

Describe alternatives you've considered

Currently, one has to export the section to a file, and then import the file to the working document. This means that model changes are less likely to be kept in sync, as this is an awkward workflow.
Exporting textual attributes seems to require writing some form of CLI export script. This is a significant barrier to more widespread usage of the models
One can use also screenshots, but these get big, and may not scale well, and don't include any attribute text.

Additional context

It seems that between cairo surfaces tkInter, and/ or one of the Python clipboard libraries, this should be possible in an OS agnostic way.