There is Favoriting (Ctrl+Click) that looks like a multi-selection, but it isn’t. It does nothing more than mark individual modules for the Favorites filter.
The browser needs Shift and Shift+Ctrl click for genuine multi-selection, with Enter to commit the selection and insert the modules, or have a menu selection of various operations on the selection:
- add to patch
- remove from patch
- favorite
- un-favorite
- hide
- un-hide
- copy list to clipboard