bug: checkerboard is not showing on Firefox
bug: checkerboard is not showing on Firefox

kennethjiang/OctoPrint-Slicer,kennethjiang/OctoPrint-Slicer,DeltaMaker/OctoPrint-Slicer,kennethjiang/OctoPrint-Slicer,DeltaMaker/OctoPrint-Slicer,eyal0/OctoPrint-Slicer,DeltaMaker/OctoPrint-Slicer,eyal0/OctoPrint-Slicer,eyal0/OctoPrint-Slicer