Exactly, not useful for this case because the Fn-key combos send no event that could be mapped, for the OS it's like no key was pressed at all... And for Left/R

Exactly, not useful for this case because the Fn-key combos send no event that could be mapped, for the OS it's like no key was pressed at all... And for Left/Right button, all other toggle-combos (Ctrl, Shift, Alt) are already natively in use and needed, so also not an option to remap them in Windows. Dell needs to patch their BIOS to fix that properly...