Some indication displaying the last active window

Upon export of, e.g., graphics, I'm always unsure whether I had the correct window active before I switched to the command line window.
A small built-in indicator signalizing this window would be great for me.
A simple idea would be alteration of the title of the command window to "'ExperimentName': 'LastActiveWindowName'" or "'ExperimentName': 'LastActiveWindowTitle'"

Opinions?
HJ