Drag & Drop within an editor window copies text instead of moving it

[zertovitch]

Drag & Drop within an editor window does copy the dragged portion of text, instead of moving it. This is especially annoying when rearranging comments: if you are not aware of the bug, you don't notice immediately the unexpected copies…

Note that when the Ctrl key is pressed during the Drag & Drop, it also does a copy, but this time it is expected.

This problem occurs at least on the Windows edition of GNAT Studio.

[zertovitch]

Another occurrence a few moments ago: I have moved "[some expression] +" to the next line for better readability and noticed only by chance that the old text was still there.
It means that "[some expression] +" would have been at two places and a nasty bug in the code would have been spuriously introduced due to GNAT Studio's bug.
Please label this issue as a BUG!

[AnthonyLeonardoGracio]

Hello,

We changed the label, but it's probably a Gtk+ bug. We can't reproduce on Linux. We'll have a look.