Input data was spoiled after typing special chars!

[YuryMisak]

When user enter special chars like a coma or PrintScreen button after select item from selectbox, input value sets to unexpected chars, e.g. ',' for PrintScreen.
Steps to reproduce:

1. Click on SelectBox
2. Select item from dropdown list
3. Click PrintScreen tab

I think, this bug located in mainClick() method, which handles keyup event.