CBMTILE coordinates around certain area behaves oddly

[ahmadayubi]

When you are over a certain area in CBMTILE the coordinates seems to point to another place on the map, as shown in the video:

2021-04-16.16-28-52.mp4

If you look at the debug panel in the bottom left, you'll notice the coordinates seem to "jump". All those values are calculated using Proj4 so I'm wondering if this is due to the projection definition?

[prushforth]

Projection mystery!