The “Form data may have changed. Are you sure you want to close this dialog?” confirmation dialog (T15034) is shown whenever any key has been pressed in the dialog, including keys which do not change anything, including Shift+Tab, Ctrl+A, Ctrl+C. (But excluding arrows and Tab, those seem to be ignored.) Selecting using mouse and copying via a right-click menu does not trigger the confirmation. And even right-clicking and pasting a text into the dialog (into some other dialog which is not read-only) does not trigger it, allowing me to close without confirmation.

Repro:

1. Go to a Diffusion repository page.
2. Click the green Clone button.
3. In the dialog, click an edit box.
4. Press Ctrl+C to copy the URL.
5. Press Esc to close the dialog.

What happens:
A confirmation dialog “Form data may have changed. Are you sure you want to close this dialog?” appears.

What should happen instead:
Nothing should be shown; by pressing Ctrl+C, I didn’t change any form data.