you can customize your webpage colors Change the fonts and colors websites use

Thanks for this. I tried this option and there is no difference. It is almost like I have a connection problem when you are using a remote monitor and the connection is not working and the fonts are all over the place. This is just an asymmetrical sets of blocks. My outlook is fine so i know it is FF that is causing the problem. I have tried to post a picture from the add images but this just constantly stays in loading mode

have you gone to color and font part of Settings for fonts, languages, pop-ups

Yes have unchecked everything, restarted and and still no change

Hi amacinty,
could you try disabling hardware acceleration?

• At the top of the Firefox window, click on the Firefox button and then select Options
• Select the Advanced panel and the General tab.
• Uncheck Use hardware acceleration when available.
• At the top of the Firefox window, click on the Firefox button and then select Exit
• Start Firefox the way you normally do.

More information can be found here:
Troubleshoot extensions, themes and hardware acceleration issues to solve common Firefox problems

Eventually got the file down to a sensible size albeit a bit small but gives you the idea of what I am looking at. The horizontal colours change as you scroll up and down

Thanks for this tried the hardware accelerator tip but it has still not changed looking at this website as per my little diagram. Still also getting the box you put the comment in changing colour by every letter.

Thought I would check when the issue started to occur. I have been on a really old version of Firefox 3.6.28. Going back to that version I do not have the colour problems. However going to version 11 the next one I get my colour issue appearing. I didn't realise I was so far away from the current standard. I will go and investigate what changes happened to get to FF 11