Just had a look and three is quite a lot going into Firefox's reader mode.
https://github.com/mozilla/readability
For the vast majority of pages you'd actually want to read, isProbablyReaderable() will quickly return a fair bool guess whether the page can be parsed or not.
For the vast majority of pages you'd actually want to read, isProbablyReaderable() will quickly return a fair bool guess whether the page can be parsed or not.