I tried googling and I got a lot of hits for what reader mode does and how to enable it, but nobody can explain what the browser is actually doing.
Do sites have pared-down versions of their pages specifically for reader mode? Or does the browser just scan for particular HTML tags?
If it helps there’s a standalone version of the logic.
At a rough scan, it looks like it tries to find a best guess “main content” node by stripping unlikely nodes and then scoring each node. Element type and content contribute to the score
/** * Loop through all paragraphs, and assign a score to them based on how content-y they look. * Then add their score to their parent node. * * A score is determined by things like number of commas, class names, etc. Maybe eventually link density. **/