I can confirm, what Bernhard says.
Kosmas, would you quickly have a look at your demo site, please?
“Homepage 1” is working fine for me.
“Homepage 2”, “Homepage 3” the bug still appears.
So it seems, it might partially be fixed. On version 1.1, “Homepage 1” had this issue also, I just double checked that.
I also switched the header overlapping option from “yes” to “default” and on theme settings to “yes”. Same result.
Maybe someone can also check it out. I am on Windows, tested with Chrome and Firefox.