You can't stream with the Firefox browser, because it's a browser and that's not its primary meaning. You can install various plug-ins to watch streams or to download videos. There are ones like VideoDownload Helper that allows you to save videos from all the known video streaming websites. However, this is something else than your inquiry.
You can try VideoDownload Helper using the following link: https://addons.mozilla.org/en-US/firefox/addon/video-downloadhelper/
Note: Click the link while using Firefox browser
