Helper/Cheat sheet for Snap Areas

I like to use the "Make snap area invisible" option for my Snap Areas. However, when I discovered "Only show snap area while holding", I expected to unveil normally hidden areas.

Well, it works differently (and I'm not saying it's bad), so I'd like to suggest the feature of highlighting snap areas while holding the defined meta key, so it can be used as a cheat sheet when using the "make snap area invisible" feature.