Another mod, called Amecs, allows you to add modifier keys to your key bindings (such as Alt+M, for example). It would be great if either (a) Controlling had this feature or (b) Controlling offered support for Amecs. When both mods are loaded, Controlling overrides this functionality. I believe it is because Fabric loads mods in alphabetical order and Controlling happens last.

As a workaround, I have found that setting funky key bindings with Amecs and only then enabling Controlling will leave those bindings working. However, they cannot be changed again until unloading Controlling. (The regular key bindings, that have no modifier keys, can still be changed as per usual.)

Also, it seems like someone opened a bug report on the Amecs bug tracker as well: Siphalor/amecs#49

Duplicate of #77