Paste (Ctrl+V) does not work in code cells

It makes impossible to copy-and-paste code, which is weird.
It works well for markdown cells.

Chrome, latest version, Version 56.0.2924.87, on Windows 7.

Currently copypaste is supported for syntactically correct code. Incorrect code can’t be pasted so far, but will be available in future. Please, post here a snippet which did not work for you.