How to disable LED on Acer ED270UP Monitor
Solution 1:
Put a piece of non-transparent tape on it.
Works on all kinds of hardware!
Solution 2:
Color the LED with black permanent marker. The ink will not be completely opaque, but will dramatically reduce the brightness of the LED. Easily wiped off with isopropanol if you dislike the result.
Solution 3:
I know you don't want tape. Use a blob of blu-tack. Lead a simple life and save brain cells for the things that matter.