Hi Nicholas Skerven,
Thanks for your post. Based on my research, Microsoft doesn’t provide such functionality that showed security banner at top of screen. Based my research, there is a classification-banner python utility at https://github.com/fcaviggia/classification-banner. It's no longer maintained, but we've been using it without change for a few years now. It's OK. One problem is that it doesn't "shrink" the desktop screen, so application windows can overlap it; it's set to Always On Top, but it would be nicer if it actually couldn't be overlaid at all.
A simple solution, of sorts, would be to change the desktop background image. This can have issues if you're displaying on multiple resolutions (I don't know if Gnome supports SVG for such purposes) and of course it can be obscured by windows covering it.
Older versions of Gnome let you create multiple bars that worked perfectly, but that disappeared - along with many other customizations - in Gnome 3.
Note: This is a non-Microsoft website. The page appears to be providing accurate, safe information. Watch out for ads on the site that may advertise products frequently classified as a PUP (Potentially Unwanted Products). Thoroughly research any product advertised on the site before you decide to download and install it. Hope this helps.
Best Regards,
Ian Xue
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