Comment 0 for bug 15224

[build 2002042908]
Suppose you have two plug-ins installed:

1. "Plug-in AAA"; MIME type "application/aaa"; extension ".aaa"
2. "Plug-in BBB"; MIME type "application/bbb"; extension ".bbb"

and you encounter an embed tag like this:
  <embed src="foo.aaa" width=100 height=100>

or an object tag like this:
  <object data="foo.aaa" width=100 height=100></object>

and the "foo.aaa" document has a MIME type of "application/bbb" (sent by the
server in a Content-Type header).

File extensions are never supposed to be used when a MIME type is present, so
the browser should look at the MIME type, and decide to run Plug-in BBB.
Mozilla, however, runs Plug-in AAA in this situation.

Mozilla behaves correctly (runs BBB) if the embed or object tag includes a
"type" attribute reflecting the MIME type, or if you view the "foo.aaa" URL
directly, or if no plug-in for extension ".aaa" is installed.

See http://entropymine.com/jason/testbed/whichplugin/ for my test page using
Flash and Acrobat. When I try it, Mozilla fails (1) and (3). Nav4 has no problem.