The installer does not place the QuickTime Plug-in in your browser's Plugin folder. The QuickTime Plug-in is placed in QuickTime Folder which is located in the root directory of your boot drive.
You need to move the QuickTime Plug-in to your browser's Plugin folder. If you have more than one browser, you need to make copies of the QuickTime Plug-in file to place in the additional browser Plugin folders.
Review your MIME (Helper) associations after adding the QuickTime Plug-in to your browser's folder. Occasionally The MIME connections get misdirected after replacing the QuickTime Plug-in. If this happens, simply reset them to QuickTime.