I don't see any yellow in my Thunderbird.

Where is it? Menus? Message lists? Message text windows? Window frames etc?

What version? What operating system?

V 31.5 latest version, but the programme is white but sits on a yellow box attached screen shot , likewise when writing a new message. I am on windows 8.1 and windows 7 same

Do none of your other programs have this yellow border/frame colour? I'd have thought that Windows has supplied the colour.

Here in Windows 7, and at home on Linux, the border is whatever colour I chose when setting up my desktop appearance settings.

I don't use Windows 8; maybe it provides different colours to different applications?

I don't know of any settings in Thunderbird to control the colour of that component; it is whatever the Operating System is set to use.

thanks you are probably correct, try and find something on windows now! I don't have any yellow borders round any other programme and my background is an image. I appreciate your time and effort in helping me.

My partner, who uses Windows 8, pointed out that it seems to take its colour from her desktop background picture. Hers is of a sunset with blue and purple hues, so she gets a lilac/mauve surround to Thunderbird. Does that seem to fit with your situation?

Indeed you are both correct the background image decided what colour and you can't change it, so have tested with lots of different backgrounds, it doesn't seem to matter if own picture, their themselves or supplied photos. A bit annoying but many Microsoft things are!!

Thanks for your time

The background color in Thunderbird is done by yourself, setting toolbar colors for your desktop or from a desktop theme, if applicable.

I used to have night time view, where the background was essentially midnight blue, and black email backgrounds with white lettering -- which I prefer

How does one get this back (I have all white now)?