Overview of AR 12719 and magnetic polarities (N1–N2 and P1–P2) before the eruption in HMI magnetogram and intensity, GST TiO and Hα, IRIS 1330 Å, and AIA 171 and 94 Å. The white and black arrows indicate the sunspots, and the yellow arrows show a magnetic cancellation site around N2. The blue and green arrows indicate the coronal loops (L1) and the filament threads of interest, respectively. The dashed blue and red boxes represent the field of view of the middle and bottom panels, respectively. Contours of HMI longitudinal magnetic fields at 18:04:20 UT are superposed on panels i with positive (negative) fields in blue (green), and the levels for positive (negative) fields are 200 (50), 400 (100), and 600 (150) gauss.