When you go to the bookmarks page of your modern web browser (any of them) and export your bookmarks, the browser will give you an HTML file — that is not actually HTML. The document type of the file exported is the Netscape Bookmark File Format. It's the format that Netscape came up with in the 90s to store bookmarks. To ensure easy switching from one browser to another, all subsequent browser releases have used this file format for importing and exporting bookmarks.
This outdated format requires a minute for the present day developer to understand, and at least a couple more to write code that extracts data from this exported bookmarks file and transforms it into a format that they can use for their project's needs.
JSON is a modern and standardized language-independent data format.
To make the job of anyone trying to use bookmarks exported from a browser in a software development scenario easier, I wrote and published bookmarks-to-json, a simple but effective piece of code that gets rid of the pain of dealing with code from decades ago.
Developers (or anyone who understands JSON) can use the npm package or the website to upload the content of their exported bookmarks and receive clean and easily understandable JSON data.