On Staggered maps, it looks like every grid line is rendered as if it were a Major Grid line, making the major grid impossible to see.

Compare Isometric vs Isometric (Staggered), no other settings changed:

Note how the grid lines in the staggered map are all as thick as the major grid lines in the non-staggered map.

Reproduce

1. Set the major grid to something larger than 1x1, but small enough that you can clearly see the major grid lines, e.g. 10x10
2. Create an Orthogonal or Isometric map that's larger than the Major Grid, so you can see the grid lines
3. Observe the clear visual distinction between regular and major grid lines
4. Change the map orientation to Isometric (Staggered) or to Hexagonal (Staggered)
5. Observe how every grid line appears thick like a major grid line

This was reported via Discord on Tiled 1.9.2 on MacOS. I was able to reproduce it in Tiled 1.9.1 (Qt5) and 2023.02.17 (Qt6) on Win10 x64.