When "D5" is released, "D0" turned to yellow on IE

[Helen09]

Repro steps:

1. Navigate to https://makecode.chibitronics.com/beta
2. Scroll down to "Love to Code" and click "Basic Switch" -> "Open Example" to open this project
3. Presse "D5" and release "D5" and then observe led "D0"

Expected result(Edge, Firefox & Chrome):
When "D5" is released, "D0" should be off

Actual result(IE):
When "D5" is released, "D0" turned to yellow on IE