H5Viewer: add fullscreen query parameter

Hibou now supports being started with the explorer collapsed by passing the fullscreen query param: https://hibou.esrf.fr/?sessionId=1c26adc5-a49f-4a17-922d-c81ba225262c&datafileId=638375087&name=/ls3027-rsd_bis-rsd_bis_cell3.h5&fullscreen
Could you please add this param to the URL of the iframe (but not of the link that opens the viewer in a new tab)?