A question about path manipulation

Blender itself seems to do something rather helpful/clever when a file using absolute paths from Windows (e.g. d:\blender\myfolder\myimage.png) is loaded on Linux. It goes looking in /d/blender/myfolder/myimage.png. This makes things nicely predictable.

I ran into an issue with DECALmachine where it stores a path as-is in the blender preferences, and then uses that value as-is whereever those preferences are loaded. On Linux, this means that it ends up creating ‘d:\blender\assets’ as the base folder name, rather than looking for /d/blender/assets. I was trying to find out how/where blender adjusts its path as described at the beginning, in order to provide a way to mirror this helpful blender behavior within the addon.

Is this done within core blender code, or via the Python API?