Would you please post a screenshot of this? I'm not sure what you mean.

here it is

I see no option for that anywhere.

Thanks David. ...Thunderbird is the only app (that I know of) that does that. For example, when you open a word document or a photoshop document or a Firefox webpage, the window title (& taskbar tab) = the opened document's title. But with Thunderbird, they added this one word+colon before the email title. It may not seem like much, but for me it makes a big difference because it eats-up the narrow space I have to see the title while providing no extra benefit at all. I know this is an email composing window, I don't need the hint ;)

re :..Thunderbird is the only app (that I know of) that does that. For example, when you open a word document or a photoshop document or a Firefox webpage, the window title (& taskbar tab) = the opened document's title.

I'm not sharing your experience. In my case all programs, document, windows or Tabs that open display the program name that opened them or the Title of window or Tab contains title.

examples: In windows search type: Photos and select it It has the program title 'Photos' and nothing else because nothing is opened. Or choose to open a photo using same program and you see: Photos - name of document So Program followed by doc title.

OpenOffice document says: name of document.odt - OpenOffice Writer Open the app called Paint: Untitled - Paint So they do the reverse - doc title followed by program.

Even Firefox for this question says: Remove "Write:" from the email composing window title (display only the email title) | Thunderbird Supportforum | Mozilla Support - Mozilla Firefox

So Firefox and Thunderbird tend to put program last. If you have set Firefox to not display Title, then the same identical information is visible in the Tab - cannot see the full title because tab too short - hover over tab.

There are options in some cases to hide the Title Bar especially when it is obvious and information is available in another way eg: in a tab. Firefox can hide the Title Bar and so can Thunderbird.

Thunderbird : Menu app icon > View > Toolbars > Toolbar Layout - uncheck 'Title Bar' Firefox: Menu app icon > More Tools > Customise Toolbar - uncheck 'Title Bar'

It can also be changed via Preferences > General > Config Editor preference: mail.tabs.drawInTitlebar = true to hide

In Thunderbird: All windows, tabs that open will display the Title in Title Bar or Tab. I've never seen empty Tabs or windows that open with no title. eg:Account Settings, Add-ons Manger, Address Book, Write, Customise Toolbar, Search Messages, Message Filters plus loads more - all of these Tabs, windows, including pop ups and error messages - all will display the title.

The 'Write' window displays: Title of window = Write: Email Subject or (no Subject) to indicate new - Program name. This aids people: who use more than one email client who may be selecting to send a document via email and they can be certain which program opened that Write window.

For those who use 'Speech Software', one of the first thing it reads and announces is the window title so user knows what has focus.

Sorry, only aware of ability to remove the Title bar in Thunderbird and Firefox main UI.