In the Arduino IDE, each tab is named with the name of the file it contains. Where the tab has been modified and not saved, the tab shows an § character after the file name. This is what I call a 'dirty' file i.e. needing to be saved.
I've noticed that when I change focus between tabs, the newly selected tab always shows as 'dirty' regardless of whether I've made any changes to it, for any tab which has ever been modified in that editing session.
For example, let's suppose I open a sketch Foo.ino which has an associated file Bar.h: the IDE shows two tabs with Foo on the left and Bar.h on the right. If I click between the tabs nothing unusual happens, each tab continues to show the file name without any §.
Now I make some change to Bar.h. When I make the change, a § character is appended to the tab name. Then I click on the down arrow button to save it, and the § disappears. Then I click on the Foo tab. It displays as normal. Then I click back on the Bar.h tab. A § is immediately appended to the tab name. I haven't made any changes in this tab since saving it, so it should not be displayed with a §.
The same problem occurs with more tabs, and it seems that the problem affects any tab which has been edited during the life of the Arduino IDE window. If I close the IDE and restart, the problem goes away (until I make any changes).
Is this a known problem? It's not a big deal, but is inconvenient when I'm editing lots of files and want to make sure I've saved them all.
I'm using Arduino IDE 1.0.4 running on Windows 7 Pro 64-bit.