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Firefox handles many types of audio and video content on web pages. This article explains which media formats you can play and how to control, save, and open them.
Table of Contents
- 1Supported formats
- 2Audio and video controls
Since the use of certain audio and video file types is restricted by patents, a third-party application is required to use them. Firefox, however, is able to play natively open media and some types of patented media.
Open media
Firefox can play the WAVcontainer format (.wav, .wave file types) containing uncompressed audio in PCM at 8 or 16 bits per sample.
Vorbis audio, Opus audio, Theora video, and VP8 video are free audio/video compression formats for use without patent restrictions. They can be viewed in Firefox if they are embedded in the following container formats: Ogg (.ogg, .oga, .ogv, .ogx, .spx, .opus file types) or WebM (.webm file type).
Firefox also supports FLAC (Free Lossless Audio Codec) playback (.flac file type) and MP3 playback (.mp3 file type).
Patented media
AAC and H.264/MPEG-4 AVC are patented audio/video compression formats. They can be viewed in Firefox using built-in OS libraries (so neither Mozilla nor you need to pay a fee) if embedded in the MP4container format (.mp4, .m4a, .m4p, .m4b, .m4r, .m4v file types).
Firefox supports WebM/VP9 video on systems that don't support MP4/H.264.
Tip: In order to test your system, some sample video files are available in the “Video For Everybody” Test Page at camendesign.com.

Control bar
When you visit a website that includes supported media, you will see controls for managing playback when you hold the mouse pointer over the media on the page.
- Play button: Starts playback.
- Pause button: Stops playback once it has started.
- Position slider: Indicates how much time has elapsed since the beginning of the file. Drag the slider left or right to go back or forward.
- Volume control: Click to mute or unmute. Hover and drag the slider up or down to adjust the volume.
- Fullscreen button: Toggles fullscreen when in default size.
- Default size button: Restores the default size when in fullscreen.

Context menu controls
The context menu (accessible via right-clickCtrl-click) includes the above controls except the sliders, and also let you:

- Accelerate or reduce the playback rate: Select Play Speed and then one of the available speeds.
- Play video over and over: Select Loop so that the video will play over and over automatically.
- Hide controls: Select Hide Controls so that the bottom control bar never show up. To show them, select Show Controls.
Keyboard controls
After you click on the media on a web page, to give it focus, you can control the playback with your keyboard.
Command | Shortcut |
---|---|
Toggle Play / Pause | Space bar |
Decrease volume | ↓ |
Increase volume | ↑ |
Mute audio | Ctrl + ↓command + ↓ |
Unmute audio | Ctrl + ↑command + ↑ |
Seek back 15 seconds | ← |
Seek back 10 % | Ctrl + ←command + ← |
Seek forward 15 seconds | → |
Seek forward 10 % | Ctrl + →command + → |
Seek to the beginning | Home |
Seek to the end | End |
To save an audio file from a web page to your computer:
- Right-clickHold down the control key while you click on the audio controls and select Save Audio As….
- Select a location on your computer to save the file.

To save a video file from a web page to your computer:
- Right-clickHold down the control key while you click on the video controls and select Save Video As….
- Select Save Snapshot As… if you only want to save the video snapshot.
- Select a location on your computer to save the file.
The media files you save from web pages may not play in your normal media player. To open these types of files:
- Open Firefox.
- Click Ctrl + Ocommand + O.
- Navigate to the folder that contains the file you want to play and click .
Firefox Mp4 Not Playing

If you are having problems with audio or video files, see:
Mp4 Player For Firefox
Last versions are avaliable now!
Full versions history is avaliable here. |
