Stacked images of all TRAPPIST viewing intervals presented in this work, cropped around Io and having undergone the processing described in Sect. 2.2 of the main article. Images are orientated with north upwards and west to the right. The direction towards the centre of Jupiter in the image is indicated by a short cyan line. The short magenta line centred on Io indicates the apparent direction of movement of Io in the image. The dashed blue ellipse represents the plane perpendicular to the local magnetic field at Io according to an observer on Earth, and the blue line between the centre of Io and the edge of this ellipse is the projection of the movement vector of Io in this plane. Green lines represent detected jet-like structures. On 23 January 2015, Io was eclipsed by Jupiter, and hence not visible.