Adding Java-Script Clipboard Transformer to the Open URL With Selection Action

Adding a Java-Script Clipboard Transformer to the Open URL With Selection action (similar to the way it is done with the Insert/Type/Paste Custom Text action) would be a great help for some use cases. Sometimes it comes very handy if one can check and/or process the selection (or clipboard) content before adding it to the URL.

Or is there a way to elegantly solve the problem with the existing options? I searched the forum longer but maybe I missed something.

Thanx, cu mc