Mentions drop down remains visible after pressing ESC to cancel inline edit

Steps to reproduce:

1. Go to any issue
2. Edit any field that supports mentions (i.e. Description)
3. Start to write a mention but do not select any user (i.e. type '@a')
4. Press ESC to cancel the inline edit

Actual result: Mentions drop down is still visible
Expected result: Mentions drop down should be closed