I find the option "accessibility"
it was already in "regular" but the bar is on top only when i open an image file.
When i choice "keep on" the bar is always on top.
When i choice "autohide" the bar is hide.
When i choice "keep on the top" the bar is on top.
But I wish that the bar is in the background when i open software, images files ect... but not invisible.