musescore/MuseScore — pull request #1561 by trig-ger (2014-12-20 11:04:58+00:00)
Title: Add Cancel button to the MIDI import panel

It helps to undo (for example, erroneous) changes in MIDI import operations that have not yet been applied.

Cancel button:
http://wstaw.org/m/2014/12/20/2014.12.21_.png