Show visual feedback "warning" when using spring-loading folders

Mac OS as far back as 8/9 had this nice "warning" flash effect when you were about to commit to a spring. It lasted maybe 3/4 of a second; the icon and text would flash and then it would open the folder. This gave just enough time to decide to commit or change your mind. It was a really useful UI addition.

Here is the example in Mac OS 8:
https://www.youtube.com/watch?v=3us0THnALQw

Here is an example of it on semi-modern macOS:
https://youtu.be/gdUPrMjlLy8?t=20

It would be nice if Files in Elementary also featured this effect.

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