If I set cells with borders of 1.50pt (or 1.25pt) thickness, the visible thickness is about double compared to the default 0.75. However, when I open the file again, the visible thicknesses are now same, and when right-clicking to “Format Cells…”, all borders appear to be of 0.75pt thickness.
Only when I set the borders to 1.75pt thick, is the thicker border stored and recalled on load.
If the thinner borders are all rounded to 0.75pt (or 1pt or whatever), I don’t think there should even be a possibility to set the borders to the in-between thicknesses.