I already had Firefox, with the Pinterest button downloaded directly from Pinterest (here: https://about.pinterest.com/en/browser-button), but I had to reinstall it from scratch (for an unrelated problem with Facebook), and now I can't reinstall the Pinterest button, everytime I try it sais there's a connection failure. I don't have connection problems with anyting else. The same thing happened when I tried to install the MEGA add-ons (but I already found a working solution here https://support.mozilla.org/en-US/questions/1130343) so I'm prone to think that's a firefox problem. I'm aware there are alternatives (even though they're not as good as the one I would like) but I would prefer to resolve this issue, since it seems to cover more than just Pinterest. Thank you.