"fixed" is a strong word, so I'll say: I wired up my broken umbrella. now, it opens.

hey, "fixing" can be an umbrella term

Extra props if you used a wire used to tie cables in electronics packaging, or a wire used to tie a bread bag, although they are probably too flimsy and bread bags now mostly use plastic clips.

If it's dumb and it works then it isn't dumb.

I love repairing umbrellas! Even the cheap ones.

My first thought, a poprivet won't work because it would compress the connection.

I didn't find an actual replacement, that sort of cheap, hollow rivet that can be fastened without compressing the joint.

A bent ring of coat hanger wire would probably do the trick. Or, a small split ring.

There is nothing more permanent than a temporary solution