This question already has an answer here:
Websites can ask permission to make themselves protocol handlers, which means that when you click on a link with a certain protocol, that link will be opened "using" that website.
How do I do this with Gmail for the
I'm using Chrome, but I hope there is some setting in Gmail that I can toggle for this, so that I don't need to ask this for every browser I use.
I looked in the Chrome settings, and there is a way to manage protocol handlers, but not to add new ones. The option can be found under the privacy settings.