An indication to know if a program is Sandboxed

[Zerokami]

Almost all Windows based sandboxing programs show an Indication that the program is Sandboxed.

# in Window title
Window border colors like Red, Yellow, Green, Purple.

Considering the fact that, if Firefox is already running, then a new Firefox opened using Firejail doesn't get sandboxed, I think it is crucial that we have some indication to know if we are protected.

[smitsohu]

for context see also #281

[netblue30]

It would be nice to have something like this but we are missing the support in the window manager. The window/desktop manager handles the window border.

[chiraag-nataraj]

@netblue30 We should be able to set the window title though, right? I think we could go with that as a stop-gap measure...

[rusty-snake]

As a workaround you could use env to set an alternative/own GTK+2, GTK+3, GTK+4, QT4, QT5 theme.