Proper motions along the loop. Similar to Fig. 4, but along the EW direction in the black rectangles in Loop 1 in Figs. 1c–g. The red dotted and dashed lines indicate upward and downward proper motions near the loop footpoints. The respective mean velocities are denoted by the numbers in the plots. The black dash-dotted lines indicate when the loop first becomes visible in the respective channel (same times as in Fig. 2). E and W are the same as in Fig. 1.