At work I run Firefox without the (great) Adblock Plus plug-in. Adblock Plus mangles the HTML code to insert its own code that displays the "Block Ad" tabs, and this interferes with our CMS. Whenever I insert some code to embed video, Adblock Plus sees it and then adds its own code, ruining the code.

I forgot this, and installed ABP and then had to uninstall it.

Then, I started noticing that TinyMCE was altering URLs in links, so a url like http://example.com/go.php?id=100&start=344 would get mangled, so the ampersand (&) was replaced with & the HTML entity. I'd see: http://example.com/go.php?id=100&start=344

It turns out this is correct behavior, because xml doesn't allow & to be in an attribute. It needs to be escaped. The only problem is that IE6 won't handle these links correctly.

It also seemed like IE 8 wasn't displaying the videos correctly, so it's possible that there's still a problem. It's just very intermittent, failing in some places and not others, so it's probably a Flash or IE 8 bug, not TinyMCE's fault.

The other weird thing I noticed is that TinyMCE behaves differently in IE 8. From the video player embed code, it strips out the EMBED tags, but leaves the OBJECT tags. Firefox leaves both in there. This bug requires more study.