System Information
Win 8.1x64, 3x gtx580

Blender Version
2.79a

Short description of error
In a node's Object parameter, on entering the text manually, after pressing enter to confirm, if the mouse happened to be located where normally the "X" button to clear the parameter is, the field gets cleared.
Also applies to other object pointer fields.

When entering names in Node Editor, (at least for me) it is common to move the mouse slightly sideways, so that the cursor is not over the field being typed in. As a result it happens to be over said clear button quite often. Given that it is currently impossible to undo a single name change T54580 , it turns into either loosing the name and having to search/type it again, or more often - by automatically pressing Undo - losing a whole row of changed fields.

• Click the Object parameter to type manually,
• Move the mouse to the right side of the field, where the "X" was located before starting to type,
• Enter a new object and press enter,
• The Object parameter field is empty.