Skip save dialog for untitled document with only blank contents
[file loading and saving][enhancement]
When an untitled document has never been modified, exiting gedit does not prompt a "save as" dialog box. However, if an untitled document is edited, then is left with empty contents, the "save as" dialog box shows. I see no reason why a user may worry about losing changes to a blank document.
I would therefore suggest to relax the condition for skipping the "save as" dialog box
- from current behavior: skip save dialog if no change has been ever made
- to a new behavior: skip save dialog if the contents is made of only spaces, tabs, and newlines.