It's different from the privacy tracking widgets. It's just a link to a little joinmastodon.org web app that helps you share it on your instance. The website that hosts the button (or link) does not load any 3rd party scripts. If you enable the option to add a logo it will add an inline SVG image. The button as seen in the blog is the creation of the blog writer and only adds a bit of CSS to make it look like a button.

The code of the web app is opensource: https://github.com/mastodon/share

The CSS of the button can be found with inspect element.

I wonder if anyone actually uses any of these. I just can't imagine finding an article or something and wanting to share it this way, but I'm also not on Mastodon or other similar networks.

Now that I think about it, this might make the most sense for link aggregators, as that's just the kind of post you'd frequently share. Hm.

ikr? Every phone and their browsers already has a dedicated share button. On desktop, it's a simple copy/paste.

No real need to add more to the already suffocating websites.

Share is in the air.