I am sorry, but that make no sense what so ever. Perhaps you might want to offer information on what add-on apparently morphs into another one.

I add /enable the "two little birds" but then it morphs to something black with white letters. I don't know what it's called though. Thanks. ( I can't get a screenshot for some reason!)

Here's what it keeps reverting to.

is this theme what you are talking about? https://addons.thunderbird.net/En-us/thunderbird/addon/two-litle-birds/?src=cb-dl-featured

Yes but I got it from the add-ons menu in Thunderbird. Downloading it doesn't help.

All that addon/theme does is put a picture along the top of Thunderbird. A pale greenish grey with a picture of two birds and sets the underlying theme to default I think.

This is the change I saw in Thunderbird when I installed it.

Your image is about a dark theme and I think is a windows setting you need to change, but I will try and offer all the choices.

This display has nothing to do with the theme you mention, and looks to me like the Thunderbird base dark theme, or the theme that follows the operating system theme (which is the default). In recent windows releases there has been a default dark theme. Personally I like black writing on white, not white writing on black, so I use Thunderbird's light theme which removes this dark stuff that comes from windows. But I also customise windows to set the appearance of applications.

I do prefer the windows task bar in black, so I try not to fiddle with the windows theme defaults much, but there are many free themes in the Microsoft store for windows and all of them may change the way Thunderbird displays lists depending if they are based on a dark theme or a light one. So I also set the windows display to always use light themes for applications.

With a bit of fiddling, I found this morning that windows 11 at least has a setting to set applications to use a light theme, i5t was probably also in Windows 120, and I missed it. I have included the windows page that allows the setting of a light application theme and suggest you set it. First you have to set the mode to custom and then it displays the option for a different setting for windows V's applications. As you can see I have the windows set to dark and the applications set to light.

I have Windows 10, not 11. I have NO idea how it changed to black with white letters. Do you know how I can change it back? I've tried and tried and can't find how to do it. Thanks so much!

It looks to me like the process is exactly the same in windows 10 and 11.

See Microsoft's instructions on how to set up their operating system https://support.microsoft.com/en-us/windows/change-colors-in-windows-d26ef4d6-819a-581c-1581-493cfcc005fe

This doesn't address my issue. I'm only referring to the dark background and white lettering in Thunderbird. Did you see my screenshot? The article you posted is for my PC in general. Hope you can help. Thanks again.

Here's a screenshot of my attempt to change the print/background but it's not working.

You can mess about in Thunderbird until the cows come home, but you are not doing anything constructive. You need to fix your windows settings to get a good result of black writing on a white background.

Or you use the Thunderbird light theme which is in the addons and Themes as a default install as it will override the poor windows settings. But in doing sop you need to forget using your pretty birds or any other theme.

It is entirely your choice.

Trying to change colors like you are doing is merely complicating matters because you will end up with other things not working because you did not take the actions you were offered to actually fix the problem. Or you will send out emails that no one can read because your message enforces a black text on a black background, because no one else has forced the issue by specifying a text colour.

I consider this topic closed. You have been advised as to what causes the issue and offered multiple ways to fix it. If you are not capable of making the necessary changes to your operating system or Thunderbird, perhaps you need to consider taking the device for professional assistance.

WOW! That was kind of mean and uncalled for. I am fairly proficient with PC's and have tried and tried and tried to make sense of what you suggest. I changed the default Windows mode to light and the default app mode to light but the Thunderbird background is STILL black! What am I doing wrong?! I really was hoping you could help.