Some interesting GNOME Shell extensions

No, I'm saying that extensions are powerful and what people write can lead to instability. Just like one would have with writing any piece of code. Same thing as extensions in a browser. Some browser extensions may not have had the peer review and testing to make a browser stable.

A good extension would go through the kind of diligence that we would have with any other module in GNOME. Without it, "caveat emptor"