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Youtube doesn't open up in fullscreen

  • 3 respostas
  • 1 has this problem
  • 1 view
  • Last reply by cor-el

tigoro
tigoro
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So, as i said youtube doesn't open up in a fullscreen, but other sites with video do. In other browsers it also opens up correctly in a fullscreen. I didn't found any special permissions for the youtube that are bloking my action for going fullscreen.

So, as i said youtube doesn't open up in a fullscreen, but other sites with video do. In other browsers it also opens up correctly in a fullscreen. I didn't found any special permissions for the youtube that are bloking my action for going fullscreen.

tigoro modificouno o

Chosen solution

Separate Security Issue, please update your Flash 26.0 r0 by removing it with this tool : https://helpx.adobe.com/flash-player/kb/uninstall-flash-player-windows.html Reinstall if you use it with Flash Player Version: 30.0.0.134 Current Version https://get.adobe.com/flashplayer/otherversions/ Step 1: Select Operating System Step 2: Select A Version (Firefox, . . . .) Note: Other software is offered in the download. <Windows Only>

Hi, try : SAFE MODE

In Firefox Safe mode these changes are effective:

  • all extensions are disabled (about:addons)
  • default theme is used (no persona)
  • userChrome.css and userContent.css are ignored (chrome folder)
  • default toolbar layout is used (file: localstore-safe.rdf)
  • Javascript JIT compilers are disabled (prefs: javascript.options.*jit)
  • hardware acceleration is disabled (Options > Advanced > General)
  • plugins are not affected
  • preferences are not affected

TEST''''is issue still there ?

If so try this : uninstall Firefox. Then Delete the Mozilla Firefox Folders in C:\Program Files , C:\Program Files(x86) & C:\ProgramData Then restart system. Then run Windows Disk Cleanup. (Note: This should be Pinned and run Weekly, If never done below expect 10's of gig's) Then run it again and click the button that says Cleanup System Files. Note: your Firefox Profile is saved. But you should make a back up before you do :

Reinstall with Current Release Firefox 61.0.1 with a Full Version Installer

Please let us know if this solved your issue or if need further assistance.

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All Replies (3)

o-o--LOKI--o-o
o-o--LOKI--o-o
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I'm on a Mac OSX 10.12.6 and YouTube videos open full screen fine for me.

Shadow110
Shadow110
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Chosen Solution

Separate Security Issue, please update your Flash 26.0 r0 by removing it with this tool : https://helpx.adobe.com/flash-player/kb/uninstall-flash-player-windows.html Reinstall if you use it with Flash Player Version: 30.0.0.134 Current Version https://get.adobe.com/flashplayer/otherversions/ Step 1: Select Operating System Step 2: Select A Version (Firefox, . . . .) Note: Other software is offered in the download. <Windows Only>

Hi, try : SAFE MODE

In Firefox Safe mode these changes are effective:

  • all extensions are disabled (about:addons)
  • default theme is used (no persona)
  • userChrome.css and userContent.css are ignored (chrome folder)
  • default toolbar layout is used (file: localstore-safe.rdf)
  • Javascript JIT compilers are disabled (prefs: javascript.options.*jit)
  • hardware acceleration is disabled (Options > Advanced > General)
  • plugins are not affected
  • preferences are not affected

TEST''''is issue still there ?

If so try this : uninstall Firefox. Then Delete the Mozilla Firefox Folders in C:\Program Files , C:\Program Files(x86) & C:\ProgramData Then restart system. Then run Windows Disk Cleanup. (Note: This should be Pinned and run Weekly, If never done below expect 10's of gig's) Then run it again and click the button that says Cleanup System Files. Note: your Firefox Profile is saved. But you should make a back up before you do :

Reinstall with Current Release Firefox 61.0.1 with a Full Version Installer

Please let us know if this solved your issue or if need further assistance.

cor-el
cor-el
  • Moderator
  • Top 10 Contributor
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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 from websites that cause problems via the "3-bar" Firefox menu button (Options/Preferences).

"Remove the Cookies" from 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 is causing the problem.

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