Clipping in Inkscape keeps visible only the (parts of) selected objects which are under the clipping object. How can I change it (invert it) so that only the (parts of) selected objects that our not under the clipping object are kept visible?
There’s no way to invert a clipping path. Use masking instead of clipping.
Create a mask and group all the objects in it. White objects in the mask will reveal the masked object, black areas will be masked to transparent. Grey objects will have semi transparency.