If I have a disconnected string input pin containing NIL and try to change the value by right-clicking the pin it doesn’t work:
Beta26: Access violation error message
Beta27: No error message but when right-clicking there’s a dark grey box instead of Input box.
Connect NIL (String) to a String Input. Disconnect link and then right-click the input.
Maybe not something you do everyday but perhaps pointing at a bug to kill.