non
Unmaximized…

Making the GNOME top panel transparent is something a lot of users like to do — but it can look a little out of place when you maximise a window.

Dynamic TopBar is a nifty little extension for the GNOME Shell desktop that “makes the top bar transparent when no window is maximized.”

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Maximized

And when one is it turns to black (or whatever colour your GNOME Shell theme specifies, assuming it styles the background-color property of the panel and doesn’t use an image file).

Through the extension’s preferences you can customise the exact degree of transparency and choose whether or to there’s a button shadow.

Revolutionary? No, but it’s a neat behaviour. The app shelf on Chrome OS does a similar thing: transparent when no window is maximised, solid black when one is. There is probably a valid design rationale written up somewhere online for why this is good UX but i just think it looks nicer!

Dynamic TopBar is a free extension and works with GNOME 3.18 and up.

Dynamic Topbar on GNOME Extensions

Download gnome extensions