There appears to be an issue with the Arduino IDE (Windows version 0015/0016) related to new tabs being marked as dirty/modified when they should not.
Steps to reproduce are as follows:
- Create a new tab
- Add code to "new tab"
- Save sketch to disk
- Move to primary tab
- Move to "new tab"
Now, "new tab" will be marked as modified although no changes were made to its code after last save. Closing and repoening the skecth appears to fix the issue. Before realizing this was an issue however I ended up searching for changes when I "knew ..." there should not be any.
Thanks for the efforts you put in to make this a valued environment!