Firefox:OS Integration:Mac OS X

In order to truly test the OS integration for Firefox builds on OS X, it's important to keep in mind that multiple versions of Firefox (in any form: trunk, branch, RTM) will confuse OS X; it generally only registers/launches the most-recently installed application, because it keys off of the "CFBundleIdentifier key from the application's Info.plist" (from cbarrett). Currently, all versions of Firefox share the same key, and thus the confusion is born.

To get around this--i.e. to truly test that the build you are testing integrates as expected--you must remove all other Firefox builds from your system.

The following is the preparatory work in order to ensure a clean environment:

To Remove Extraneous Builds of Firefox:

1. Find where each Firefox instance is installed (Spotlight helps here; be sure to search for the application/binary name as it exists on-disk, such as: BonEcho, Minefield, Firefox, etc.)

2. Drag it to the Trash can (I'd also empty the trash, just to be triple sure it's removed). Note that you can verify it's a package with contents (since it won't look like a folder) by choosing "Show Package Contents" from the Firefox build's context menu.

3. Keep repeating steps 1 and 2 until all that you're left with on-disk is the version of Firefox you wish to test.

After removing the other variants of Firefox, return to Safari's "Preferences" menu and ensure that only the version of Firefox you are currently testing is visible/selected.