When you open a video in facebook, you're redirected to mobile version so that it can play in HTML5 player
When you open a facebook video page (will not work if you click on a video and it pops-up) you are redirected to the mobile version of the site where video can be played with an HTML5 player. The desktop version of the site only supports Flash videos unfortunately.
You need to go to the video page like one of these:
Usually when you see videos on your timeline, you need to click on the "video" link at the top of the post. See the screenshots.
Troubleshooting: If you are not redirected automatically to the mobile version, when you have opened a video page, then try refreshing while on the video page. In the past it was not working when right clicking on a video link. But I've implemented an event listener to catch such events. At the moment script should always redirect, but I don't know how reliable it is in all situations and browser versions. For more details please see outdated limitation below:
When you navigate to a video by right clicking on a link to video page it does not redirect automstically. You need to click browser refresh. If you directly open a video link or open it in a new tab/window, then it works automatically.
The issue is that greasemonkey does not trigger script by every URL change. When the web site uses HTML5 functions to change current location, that is not handled by greasemonkey. So it is required some more advanced hooking to the page events that I couldn't figure out in a reasonable time. So I'm giving up, it works good enough for me. Contributions are welcome. See issue 2135 if you'd like to read more details.
