Looking at your image - I presume you mean you have white text on a white background (based on the Formatting bar squares for text and background), so cannot see any content ?

That usually occurs when the content of the email you are forwarding has some html css which specifies either the font colour or the background colour but not both.

What OS are you using? What version of Thunderbird are you using? In Thunderbird, what theme are you using? 'Dark', 'Light' or 'System theme' ? OR are you using an addon theme - if yes - what is it?

What settings have you got in the following locations - please post images showing the settings. If version 128*

• Settings > General
• scroll to 'Language & Appearance'
• Click on 'colours' button
• upload image of colour settings

If version 128* or later eg: 142*

• Settings > Composition
• Under 'HTML Style'
• Please upload image showing all the settings under 'HTML Style.

If using 142* In Message Pane header area - have you selected the dark or light toggle option to read emails?

Usually, when you click on 'Forward', the Write composing window usually says '....Forwarded Message....' followed by a table containing Subject Date From and To. That table is also visible using red colour to display the rows and columns etc of the table - it is missing - is that because you have deliberately removed it from view - edited it or added additional empty lines to hide it? I cannot tell because you have not included the right side of window, so no scroll bar?

It happens when forwarding an email on 128.13.0esr (64-bit) on Fedora 42. The forwarded email has these settings:

Thanks for letting me know you use OS Fedora 42. I presume you have no issues when creating a new email, but do you normally use white font on black or black font on white ?

When using 'Forward' on a particular emails, I can see you have white on white in the Composing Write window, which is not helpful, but I need to know what settings you are using. Please post images showing the settings.

• Settings > General
• scroll to 'Language & Appearance'
• Click on 'colours' button
• upload image of colour settings

• Settings > Composition
• Under 'HTML Style'
• Please upload image showing all the settings under 'HTML Style.

Once I know what settings you are using then I can modify what I'm using to see if I can replicate the issue or whether there is a bug report or whether I can find a fix.

It's probably caused by the css html content of the email you are trying to forward and it's clashing with a setting.

Not sure what you mean. These here:

re :Not sure what you mean.

• Settings > General
• scroll to 'Language & Appearance'
• Click on 'colours' button
• upload image of colour settings

Example image has been attached below. I need you to post an image which looks like mine showing what you see in that same location.

In the meantime... You have posted an image for the second part:

• Settings > Composition
• Under 'HTML Style'
• Please upload image showing all the settings under 'HTML Style.

In that image - the checkbox that says 'Use readers default colors' is selected.

That means when using dark mode - force the font to white and force the background to dark. This would be the default for any new email you are composing and for emails that you reply for forward if they were plain text or contained correct css html. But on occasions the css html in a received email is not exactly as good as you would wish and that means when you click on 'Forward or Reply' it can effect what is seen as that forwarded email.

Your settings via Menu Bar toolbar 'View' > 'Message Body as' can also effect what you see in a 'Forward or Reply' email you want to compose.

But I'm assuming you use 'View' > 'Message Body as' > Original HTML'

In Settings > Composition Under 'HTML Style' Please uncheck that checkbox for 'Use readers default colors' so it's not selected. Then click on the Forward button - does it look better?

So I keep everything as is but change the Override the colors... setting to "Never"?