To test how YouTube works with Firefox "uncustomized", could you do a three-minute experiment?

Create a new Firefox profile

A new profile will have your system-installed plugins (e.g., Flash) and extensions (e.g., security suite toolbars), but no themes, other extensions, or other customizations. It also should have completely fresh settings databases and a fresh cache folder.

Exit Firefox and start up in the Profile Manager using Start > search box (or Run):

firefox.exe -P

Do not delete anything in this dialog

Any time you want to switch profiles, exit Firefox and return to this dialog.

Click the Create Profile button, assign a name like Sept15, and skip the option to change the folder location. Then start Firefox in the new profile you created.

Does YouTube work any differently in the new profile?

When returning to the Profile Manager, you might be tempted to use the Delete Profile button. But... it's a bit too easy to accidentally delete your "real" profile, so I recommend resisting the temptation. If you do want to clean up later, I suggest making a backup of all your profiles first in case something were to go wrong.

Your new profile will pick up plugins from your system, from Flash to ZoneAlarm. Firefox 30 switched many plugins from "Always Activate" to "Ask to Activate". The purpose of this change was to require your permission for untrusted sites to use plugins. However, some plugins that affect the user interface and/or operate globally on all pages do not work well with this setting and unpredictable UI breakage can result.

Could you review your plugins as follows:

Open the Add-ons page using either:

• Ctrl+Shift+a
• "3-bar" menu button (or Tools menu) > Add-ons

In the left column, click Plugins. Then I suggest:

• For in-page "player-type" plugins like Flash, Silverlight, or Java, no changes are needed
• For global plugins like fingerprint readers or security software, switch to either:
  • "Always Activate" if you use this plugin on a regular basis
  • "Never Activate" if this plugin is not important or very rarely used

This might not take effect immediately in the current window, but should work in new windows, or after you exit and restart Firefox.

Does that help at all?

Thanks for reply,

YouTube and other website videos, news etc. work fine. The problem is with Facebook's UPLOADED videos on the timeline or albums from others or my own not loading - black screen. YouTube videos posted will play on the timeline with no problem or open and play on YouTube.

The problem still persisted as soon as I updated to FF 32 and Flash 15, everything else is current. When I updated, I immediately cleaned the cookies and cache and no luck. The THEME is DEFAULT so there is no custom theme. I've deactivated the firewall and all add-blockers etc. I don't really have that many more "plugins" other than Google talk and Garmin GPS map loader.

Is creating a new profile going to do much more a fresh update and turning everything off should solve.

I see this has been a problem with Facebook here and there even with other browsers and not so sure it's not a combined problems with browser, website, and graphics and hardware problems. This desktop never worked well with hardware acceleration on with FF but no problems whit Chrome until updating to 28, the first time I ever turned it back on. I none of the other laptops had trouble with hardware acceleration on with Firefox.

Firefox 32 is working fine with this one glitch and may be more Facebook and Flash problems than browser. I may try the other three laptops and see also as this may also be an issue with the monitor, graphics card and drivers on this older machine.

The new profile test is fairly quick and far easier than recording all custom settings, resetting them to defaults, and then changing them back.

Is there a mixed content blocking icon in the address bar when this happens? Looks like a shield. This article has more info: Mixed content blocking in Firefox

If you right-click the non-playing video, do you get a Flash player context menu? If you get a regular Firefox menu, the issue could be with playing MPEG video in the native HTML5 video player instead of with the Flash plugin.

Thanks for your help.

The more forums I see on this, the more variable solutions, some that worked for some and did not for others, none for me.

Rather than continue to experiment, I found something that did work even better than the original direct play back from within Facebook. The files appear to be stored as .mp4s. Clicking on the photo's OPTIONS, DOWNLOAD HD and OPEN WITH my local FLV player produces a much better quality audio and video than before.

YouTube videos are not a problem, this is only with my own uploaded videos and similar post by others in my timeline.

Here's a better description. Clicking on the OPTIONS, (lower left) then DOWNLOAD HD from the menu. I have the .mp4s to automatically open with my FLV player, eliminating BROWSE ing an application every time.

The only problem (link), with the video page still open, FF is still chewing up some CPU usage, top left arrow. Closing out the window out back to the the main album page (upper right arrow) brings this down to around 03 and the player much smoother. I've seen this hit as high as 93% CPU usage before with the window still open.

I think Facebook's entire problem is centerd around this page either not downloading or failing to launch a player.

https://app.box.com/s/mglrppwoq1dyxn16zc9r

This DOWNLOAD feature works great on my own uploaded videos. Friends' video's can't be downloaded under OPTIONS but you can EMBED POST and it opens up the Facebook player - go figure.

When I hit EMBED POST on my own videos, it says there is nothing there, a problems I saw others reporting, yet I can downlaod and play the video under the file name .mp4 Facebook has it list as.

One last note, all my own videos are FRIENDS only viewing. When set to PUBLIC, I can open under OPTIONS/EMBED POST with the Facebook player and comments shown. Otherwise, it says the video is not there under FRIENDS.

This is starting to sound like a permission issue between Facebook and the browser. I've already been through the PAGE INFO looking for any unusual changes and even TEMPORARILY broadened up some security and privacy settings with no luck so put them back.

To make a long story short, I can see my own videos either way.

NEW PROFILE

I wanted to check the effect of a new profile as you suggested. Rather than create one here, I logged off my account and logged on to the GUEST ACCOUNT which has hardly ever been used and never with Firefox until now. I launched bare-bones FF, went to Facebook and was able to play the videos direct with no problem.

One of the things I noticed is in the task manager on the guest account the plugin container was about 32 MB when the video was playing, on the main profile screen capture above, it is 0 form the same page. This sounds like Flash is not launching.

FLASH - "GLOBAL STORAGE SETTINGS" SOLUTIONS

I went to Flash's control panel website. It is considerably more extensive than the one that pulls up with a "right click" of the mouse on the video. [[Flash Control Panel|http://www.macromedia.com/support/documentation/en/flashplayer/help/settings_manager02.html]]

I saved this as a bookmark to find my way back if needed

I "loosened up" a couple of the permission settings and now it works fine.

The one that makes it work or not for is the second folder, Global Storage Settings, and checked the box - "Allow third party Flash content to store data on your computer." The slider bar is still set to 0.

I had tried this on the limited standard control LOCAL setting (right click on the vidoe) earlier and no luck. There is nothing on the GLOBAL setting panel for it.

All the settings are back to original with the exception of the one listed above on the second folder and it works fine. The second box, Store common Flash components, was already checked.

The video and audio quality is a just as good as my local player.

This must have happened with the last update.

ADBLOCK PLUS SOLUTION

Here is an example of someone else's problem and solution with a a FLASH PLAYER update from a while back. http://forums.techguy.org/web-email/869690-firefox-wont-play-facebook-video.html

One advantage of having TASK MANAGER constantly running in the background, I can tell what is too much, or no, CPU usage at all times with the browser and/or plugin container. Keeping the process sorted in alphabetical order makes it easier for general checks with the option to sort by CPU usage from highest to lowest. Same for any process.

Typically, when I'm not doing anything, neither should Firefox which is usually 3% - 4% CPU usage except for a few momentary push notifications from emails and Facebook if loaded.

Whereas a lot of people on this forum reported high CPU usage and freezes, etc. they never reported whether it was the browser, plugin container or both to give an idea of where to start troubleshooting.

In my own case above, there was no CPU usage on with the plugin container on my main profile with the black video screens and a varying 37% + on the alternate profile when it was working. This was one possible indication that Flash was not ruining, possibly an indication that the video never downloaded with the new update discrepancies.

I had this same problem in FF 33.0.2, in which clicking on the video 'play' button just gave a rotating band of 3 bars, no action, and I thought Mike's suggestion about "Global Storage Settings" wouldn't fix it, because it already had "Allow third-party flash content to store data on your computer" checked, with 100 KB allowed, so I bumped it to 1MB, with no IMMEDIATE (apparent?) solution; so I tried a related fix, "Website storage settings", found the Facebook site there (fbstatic....), & set IT to 1MB, which I THOUGHT also did not fix it.

But then I CLOSED FB (not FF!), and reopened it, and NOW IT WORKS!

So to test if it was re-starting FB that fixed it, I reset the "Global Storage Settings" back to 100KB, also "Website storage settings" for FB back to 100KB, closed & reopened FB, and it STILL WORKS!

Not sure what's going on, but it does look fixable.