I am trying to detect if a web page has Flash on it and I am currently looking for the existence of ".swf" in page content. I tried checking "application/x-shockwave-flash" but some web pages with Flash don't have that. I also found a website that uses Flash with no reference to Flash in any way. So, is there a way to make sure that a web page has Flash on it?
I don't know if this is foolproof, but the NoScript add-on for Firefox blocks Flash, and where there's Flash content on the page, it displays the Flash "F" symbol.
So, I should check that add-on and try to figure out how it manages it. Thanks for the idea.
I was really just thinking that if you install the add-on and visit the site, it will hopefully indicate any Flash objects (which you can then enable to see what they are).