Colour-composite Euclid image (red: H_E, green: J_E + H_E, blue: I_E) of the galaxy cluster A2390. The MUSE footprint is shown in red. The spectroscopic (photometric) cluster members are represented with cyan circles (boxes). The 22 cluster members for which we measured the stellar velocity dispersion are further marked with cyan crosses. The spectroscopically confirmed (photometric) multiple images included in our analysis are also shown in magenta (yellow). The multiple images are also labelled with their ID (see Table 1). The positions of the BCG and galaxy G29 (see Sect. 4) are also marked.