Hi Psygorn,

re:
> Could we have an ability to extract edges as individual curves when we press
> Join on them? ( I know Join does that for polyline edges but it seems it doesn't
> do it with single edges or for example bases of a Cylinder) ( see the green line
> in the attached file)

Join is focused on combining multiple objects together and so it ignores a single
object input.

You can extract edges as individual curves by selecting them and using
Ctrl+C/Ctrl+V copy/paste on them. That will work with any kind of edge selection.


> Also Could we have an ability to quickly extract intersection line of two colliding
> surfaces? (see the red line in the attached file)

You can do that now by selecting your 2 surfaces and then run the Construct > Curve >
isect command. That command generates curves or points at the intersections
between objects.

- Michael