What is the reason for these symbols?

Question

css

It appears in different places in the code, in Atom there is no symbol, but in Sublime it's great to see these squares. Encoding in Atom - UTF - 8. Who faced and what could be the reason? Does this fateful sign mean switching to sublime/webstorm?

upd: the screen is more suitable here, apparently =)

Answer 1

Copy-paste with formatting or special characters.