I’ve found this related topic about custom images in menus. So good and works so far.
But if i only need images for some menu items and not for everyone some code like this appears
<img alt="Image" src="data:image/svg+xml;base64,PHN2ZyB4bWxucz0naHR0cDovL3d3dy53My5vcmcvMjAwMC9zdmcnIHdpZHRoPSc0OHB4JyBoZWlnaHQ9JzQ4cHgnIHZpZXdCb3g9JzAgMCA0OCA0OCcgdmVyc2lvbj0nMS4xJz48cmVjdCBmaWxsPSdyZ2JhKDAsIDAsIDAsIDAuMzUpJyB4PScwJyB5PScwJyB3aWR0aD0nNDgnIGhlaWdodD0nNDgnPjwvcmVjdD48L3N2Zz4=" width="24" height="24">
… and it creates a empty box left of the menu text:
and it seems it’s coming from the width and height of “24” from the img tag