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.

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

VTT subtitles are shown double in latest Firefox

  • 2 replies
  • 1 has this problem
  • 1 view
  • Last reply by daniel60

more options

When I play a video in the latest Firefox (Windows or Mac) from the streaming service www.cineasterna.com the VTT-subtitle are shown double.

This issue did not occur in previous version of Firefox. The subtitles works fine and does not show double in other browsers (Chrome, Safari, Edge, IE).

Why is that?

When I play a video in the latest Firefox (Windows or Mac) from the streaming service www.cineasterna.com the VTT-subtitle are shown double. This issue did not occur in previous version of Firefox. The subtitles works fine and does not show double in other browsers (Chrome, Safari, Edge, IE). Why is that?
Attached screenshots

All Replies (2)

more options

You can try these steps in case of issues with web pages:

You can reload web page(s) and bypass the cache to refresh possibly outdated or corrupted files.

  • hold down the Shift key and left-click the Reload button
  • press "Ctrl + F5" or press "Ctrl + Shift + R" (Windows,Linux)
  • press "Command + Shift + R" (Mac)

Clear the Cache and remove the Cookies for websites that cause problems via the "3-bar" Firefox menu button (Options/Preferences).

"Remove the Cookies" for websites that cause problems:

  • Options/Preferences -> Privacy & Security
    Cookies and Site Data -> Manage Data

"Clear the Cache":

  • Options/Preferences -> Privacy & Security
    Cookies and Site Data -> Clear Data -> Cached Web Content: Clear

Start Firefox in Safe Mode to check if one of the extensions ("3-bar" menu button or Tools -> Add-ons -> Extensions) or if hardware acceleration is causing the problem.

  • switch to the DEFAULT theme: "3-bar" menu button or Tools -> Add-ons -> Themes
  • do NOT click the "Refresh Firefox" button on the Safe Mode start window
more options

Thanks, but that did not solve my problem.