Infact it works with the layerslider block, even with sound and autoplay turned on.

so actually I would like to have a slider mixed with images and videos. In the video slide I turn off the autoplay. Still it doesn`t work on mobile

so I found this pencil now (first you have to leave the full sceen mode), but once I changed something, all blocks where I previously used this custom element are not changed, only the ones in future. Any workaround for that?