Hi peterfin0, Distortion sounds like a graphics issue. Can you please try these troubleshooting tips:

1. Does it happen in Firefox Safe Mode: Diagnose Firefox issues using Troubleshoot Mode
2. Upgrade your graphics drivers to use hardware acceleration and WebGL

guigs2 said

Hi peterfin0, Distortion sounds like a graphics issue. Can you please try these troubleshooting tips:

1. Does it happen in Firefox Safe Mode: Diagnose Firefox issues using Troubleshoot Mode
2. Upgrade your graphics drivers to use hardware acceleration and WebGL

Yes, it happens in Safe Mode and Refresh does not help. The problem is associated with Firefox and only with Firefox.

Yes, it happens in Safe Mode and Refresh does not help. The problem is associated with Firefox and only with Firefox. I don't understand Option 2.

Option two is to troubleshoot hardware acceleration, however this is disabled in Safe Mode. Please update your plugins to the latest version. Check to make sure you are up to date:

• https://www.mozilla.org/en-US/plugincheck/

If you see any issues also see:

• Troubleshoot extensions, themes and hardware acceleration issues to solve common Firefox problems

Problem not solved. Plug-ins and drivers are all up to date. Can't find solution in Troubleshoot, either. Very strange. Mozilla display is readable but colors are 'washed out' and distorted.

There is a gfx color manager about:config entry that does something similar, can you please provide the troubleshooting information to check if this entry has been changed? It might not be an entry that changes back to default in Safe Mode.

You can try to disable color management to test if it is caused by a problem with color management.

You can set the gfx.color_management.mode pref to 0 on the about:config page to disable Color Management. You need to close and restart Firefox to make the change effective.

See:

• http://kb.mozillazine.org/gfx.color_management.mode

You can open the about:config page via the location/address bar. You can accept the warning and click "I'll be careful" to continue.

• http://kb.mozillazine.org/about:config

Can you attach a screenshot?

• http://en.wikipedia.org/wiki/Screenshot
• https://support.mozilla.org/kb/how-do-i-create-screenshot-my-problem

• Use a compressed image type like PNG or JPG to save the screenshot
• Make sure that you do not exceed the maximum size of 1 MB

Screen shots herewith. The problem only occurs with Firefox. Chrome and IE are no problem.

Did you try to disable color management in Firefox?

Changing the color management mode to 0 had no effect. Should I change it back to 2?

Yes, you can reset the pref via the right-click context menu to the default value.

Make sure that you do not run Firefox in compatibility mode. You can open the Properties of the Firefox desktop shortcut via the right-click context menu and check the "Compatibility" tab. Make sure that all items are deselected in the "Compatibility" tab of the Properties window.

Problem solved when I unticked the 'Run in 256 colors' box in the Properties > Compatibility tab.

Thanks Cor-el, it's taken 2-3 months to arrive at that simple solution. I have always run Firefox in 256 colors though; why is it a problem now?

peterfin0 said

I have always run Firefox in 256 colors though; why is it a problem now?

Why?

Yes, why?

I was referring to the run Firefox in 256 colours. Only reason I can think of is this is on a terminal.

Ah, I misunderstood the question. I don't know why I have always run with 256 colors. It seemed to be the default setting and no one has suggested it could cause problems. Anyhow all is well again and I can close Chrome. Thanks.