This site will have limited functionality while we undergo maintenance to improve your experience. If an article doesn't solve your issue and you want to ask a question, we have our support community waiting to help you at @FirefoxSupport on Twitter and/r/firefox on Reddit.

Avatar for Username

Search Support

Avoid support scams. We will never ask you to call or text a phone number or share personal information. Please report suspicious activity using the “Report Abuse” option.

Learn More

Hierdie gesprek is in die argief. Vra asseblief 'n nuwe vraag as jy hulp nodig het.

Mozilla Firefox on iMac not reading mp4 format.

dumitrugalit
dumitrugalit
more options

Hello, we are working on a wordpress theme and we found a little issue. When we try to access a webpage from a iMac using Mozilla Firefox, the video from our slider doesn't work. And we don't have any clue how to make it compatible with this browser.

p.s. on other browser we didn't had any issues with this.

Thank you!

Kind Regards, Dumitru.

Hello, we are working on a wordpress theme and we found a little issue. When we try to access a webpage from a iMac using Mozilla Firefox, the video from our slider doesn't work. And we don't have any clue how to make it compatible with this browser. p.s. on other browser we didn't had any issues with this. Thank you! Kind Regards, Dumitru.

All Replies (1)

jscher2000 - Support Volunteer
jscher2000 - Support Volunteer
  • Top 25 Contributor
more options

Firefox does not come with an MPEG decoder built-in (for patent-related reasons, I think), but instead will use features provided by the operating system, where available. Unfortunately, MacOS X is lagging Windows and Linux in this area. You may need to code the slider to use a plugin (Flash, QuickTime, etc.) as a fallback method of playback.