I have some z/x/y.png map tiles. While in the old days tiles were 256x256 pixels, nowadays it is not unusual to have images referencing the same extents in higher resolution (sometimes called "retina" in marketing speak).
This means the tile 1/2/3.png would represent the same geographical area in both cases but rendered in different resolutions.
When I tried to convert my directory tree to a mbtiles file with mb-util, the resulting file displays nothing in QGIS. Does the mbtiles format support higher resolution tiles and can I turn such files into a mbtiles file with mb-util?