Sometimes, and seemingly at random, typing text overwrites anything anything in front of the caret, e.g., if I have the line "print 'Hello world'" and I place the cursor in front of 'Hello world' to and type an opening paren, the line will become (Hello world' - i.e., the opening quote has been typed over. If I continue to type, I will continue to replace the characters in the string. This continues until I restart pycharm, and sometimes happens a few times a day, and I am not sure why. Is this a setting that I am turning on with a key combination, or is it a bug? Thank you!