title: Diagnosing body.onload not being called
body: <p>I have some web pages which rely on <code>body.onload</code> (or, equivalently, <code>window.onload</code>) to set them up properly. Sometimes <code>onload</code> is not being called.</p>
  
  <p>Is there a trick with some web browser (ideally Chrome, where this apparently happens most often) which will tell me <strong>what exactly is preventing the page from loading</strong> successfully?</p>
  
  <p>Clue: this rarely (maybe even never) happens when I hit F5 to reload the whole page, but more generally it happens if a page has been arrived-at by clicking a link or pasting the url into the address bar. Is there a quirk of <code>onload</code> semantics that might be tripping me up?</p>
  
  <p>N.B. The scripts themselves are not producing any errors in the console.</p>