Many users like hidden system titlebar as Firefox feature although it’s not finished yet. But we’re very close and I hope to have Firefox 64 in shape that the title bar can be disabled by default at least on Gnome and matches Firefox outfit at Windows and Mac.
Thunderbird 60 was finally released for Fedora and comes with a basic version of the feature as it was introduced at Firefox 60 ESR. There’s a simple checkbox at “Customize” page at Firefox but Thunderbird is missing an easy switch.
To disable the title bar at Thunderbird 60, you need to go to system menu Edit -> Preferences and choose Advanced tab. Then click at Config Editor at page left bottom corner, open it and look for mail.tabs.drawInTitlebar. Double clik on it and your bird should be titleless π
Martin Stransky's Blog 
Yes, the hidden system titlebar in Gnome (Fedora) is so amazing! As is the dark theme! Looking forward to FF64! Thanks for all that you and the team do!!
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Nice, thanks. How about the “Menu Bar”?
When I go to: ‘View’ -> ‘Toolbars’ there is no option (to uncheck) for Menu Toolbar?!
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Yes, the GUI is still a bit raw. You can click by right mouse button next to tabs (it’s a drag space) and you should get popup menu where is “Menu Bar” entry.
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Yeeeeeah!
For those of us who has screen resolutions of 1366×768 it is great!
Thank you!!!
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Actually, this tip was handy, but for the OPPOSITE reason. For some stupid reason TBird decided to *hide* my toolbar, and I wanted it back. So setting this to “false” brought it back.
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Yes, that settings is perhaps inherited from Firefox base.
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Thanks!! Works June 2020
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Thank you.
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