Context figures of the filament. The grid spaces mark 15°. Left: image in AIA 193 Å, on 2013 Sept. 29, at 00:00 UT. Image is clipped from 50 to 5000 DN. The filament is located on 20N 15W, with two coronal holes surrounding it on coordinates 40N 20W (CH1) and 0N 7W (CH2). Right: context image showing a derotated AIA 304 Å image displaying the filament, and the positive polarity (in green) and negative (blue). Different colour shades are explained in caption of Fig. 2. The bipolar flux emergence occurrence is located at [250′′, 200′′], enclosed in a white square. A movie available online shows the temporal evolution of the whole visible hemisphere from 21:00 to 22:09 UT in the AIA 304 Å channel. In the movie, the FOV of the right panel of this figure is marked by a black rectangle, and the emergence by a white square. The green and blue contours have the same meaning as in the right panel.