I've defined a couple of gadgets in , but they don't appear in [[Special:Gadgets]]  as one would expect. I have tried with simpler commands, but nothing seems to work. Everything related to gadgets in [[Special:Version]] seems to be the same as Meta and no.wikipedia.org, so I have no idea what's wrong.
One desperate and illogical attempt later I made it work. By putting the stuff in  instead it worked. We had the same problem with T119998. I don't know why this works, but it the important thing is that it works.