Tile generation problem for small WMS extent

[borodaev]

I've created the issue, but maybe someone can help me here
The workaround now is to use custom projection

Environment
Latest version
Custom WMS based on MapServer

Context
Rendering simple (not georeferenced) image using WMS
Using EPSG:3857
Using this extent fro both planar view and wms source:
{
crs: "EPSG:3857"
east: 5184
north: 3888
south: 0
west: 0
zoom: 0
}

Steps to Reproduce (for bugs)
Zoom to extent

Expected Behavior
Correct tile generation

Actual Behavior
I see duplicates of tiles

Possible Cause/Fix/Solution
in /Core/Geographic/Extent.js
in tiledCovering method (check line: "tmsCoord.divide(globalDimension).multiply(countTiles).floor();")
I got the same row/col tile mesh extent for different E-N-S-W extents
for example:

for
{
crs: "EPSG:3857"
east: 5184
north: 1944
south: 972
west: 3888
zoom: 2
}
and for
{
crs: "EPSG:3857"
east: 5184
north: 972
south: 0
west: 3888
zoom: 2
}
I got the same row/col extent:
{
col: 8193
crs: "TMS:3857"
row: 8191
zoom: 14
}