As the code stands in May ’20 the trigger function (isProbablyReaderable) scores only p or pre elements and div elements that contain at least one decedent br. A slight oversimplification of the scoring heuristic is: For each element in [‘p’, ‘pre’, ‘div > br’]: If textContent length is > 140 chars, increase score by sqrt(length … Read more
You need at least one <p> tag around the text, that you want to see in Reader View, and at least 516 characters in 7 words inside the text. for example this will trigger the ReaderView: <body> <p> 123456789012345678901234567890123456789012345678901234567890123456789012345678901234567890123456789 123456789012345678901234567890123456789012345678901234567890123456789012345678901234567890123456789 123456789012345678901234567890123456789012345678901234567890123456789012345678901234567890123456789 123456789012345678901234567890123456789012345678901234567890123456789012345678901234567890123456789 123456789012345678901234567890123456789012345678901234567890123456789012345678901234567890123456789 123456789 123456 </p> </body> See my example at https://stackoverflow.com/a/30750212/1069083