You can do this with karabiner-elements (https://karabiner-elements.pqrs.org/ https://karabiner-elements.pqrs.org/) by remapping cmd-l to cmd-d. I believe you

You can do this with karabiner-elements (https://karabiner-elements.pqrs.org/ https://karabiner-elements.pqrs.org/) by remapping cmd-l to cmd-d. I believe you can even add a condition to make the mapping only active in firefox, but I haven't tested that. Here is a rule that does it (only for left command, but that's probably sufficient): https://genesy.github.io/karabiner-complex-rules-generator/#eyJ0aXRsZSI6ImNtZC1kIHRvIGNtZC1sIiwicnVsZXMiOlt7ImRlc2NyaXB0aW9uIjoiIiwibWFuaXB1bGF0b3JzIjpbeyJ0eXBlIjoiYmFzaWMiLCJmcm9tIjp7Im1vZGlmaWVycyI6eyJtYW5kYXRvcnkiOlsibGVmdF9ndWkiXX0sImtleV9jb2RlIjoiZCJ9LCJ0byI6W3sicmVwZWF0Ijp0cnVlLCJtb2RpZmllcnMiOlsibGVmdF9ndWkiXX1dfV19XX0= https://genesy.github.io/karabiner-complex-rules-generator/#...