Let's say you have a website - your_website.tld - and you want people to log in to it using their Mastodon account. For a traditional social-media site like Twitter or Facebook, you would create an OAuth app on the service that you want. But there are hundreds of Mastodon servers. So you need to create a new app for each one. That sounds hard, but it isn't. Well… not too hard. Here's some code adapted from Infosec.press. It's all written using cURL on the command line - so you should be a…