DOES NOT WORK Puntuado con 1 de 5 estrellas

I have tried installing and reinstalling this multiple times over the last couple months, and it fails to work. No matter how many times I restart Firefox and my computer, it still doesn't work. I have this same app on Chrome, and it works fine, but with Firefox is does absolutely nothing.

Not working Puntuado con 1 de 5 estrellas

As the title says.

Puntuado con 3 de 5 estrellas

Doesn't seem to work for me in Firefox (although it does in Chrome).

Very good, I would like to have more applications on the labels. Puntuado con 4 de 5 estrellas

This is very functional, but It would be nice also an add-on to keep the labels for each publication, so that one does not have to rewrite them.