Comment 2 for bug 171917

Guides are a very powerful tool and I use them a lot.
I agree with the request of adding a "clear all guides" operation, wherever you feel it's easier to implement. Just to avoid having to ctrl+click over them one by one (given it's not so easy as you have a small amount of pixels and maybe a lot of different objects all around).

Also, I'd like to add three other requests:

1st: duplicate an existing guide (shift+drag, ctrl+c / ctrl+v, ctrl+d or whatever...); it would be useful for when you need to create many guides with angles different than 0°, 90° and 45°.

2nd: remember the last setting of the "Guideline - Relative change" option: I use it a lot and I need to set it each time I open the dialog. Or maybe a shift+dbl-click or alt+dlb-click could open it whith this option already set.

3rd: merge the first two, i.e. duplicate an existing guide applying an offset to the newly created one.

Incidentally, my 2nd and 3rd requests are simply a workaround for the lack of possibility to place the space origin in a given point...