Hey Blender fam! If anyone wants the OG color-checker map from Blender as an actual Texture and not just a Tester Map, I re-created it in Photoshop! Now you can actually place
Default UV Checker in "Viewport Overlays" — Right-Click Select
Quick UV Checkers - Free Blender Addon
UV Map Checkers - 3dlab.bg - Free textures to check UVs on your 3D Model
Checker Texture Node — Blender Manual
TexTools for Blender - Page 3 — polycount
texturing - How Can I make the World background Material to be checker Texture? - Blender Stack Exchange
Blender 2.8 Checkered Texture - YouTube
How to make Blender Checkers as Texture - cgian.com
How can i see my UV checker grid on my object? - Materials and Textures - Blender Artists Community