Looks like a technical drawing board: small squares forming a nice grid.
Source We Are Pixel8
Geometric triangles seem to be quite hot these days.
Source Pixeden
A pattern derived from repeating unit cells each derived from part of a mosaic in paint.net. The starting point for the mosaic was a picture of some prawns!
Source Firkin
After 1 comes 2, same but different. You get the idea.
Source Hendrik Lammers
A background tile for web with abstract repeating texture of dark "stone wall".
Source V. Hartikainen
A seamless pattern from a tile made from a jpg on Pixabay. To get the tile select the rectangle in Inkscape and use shift-alt-i.
Source Firkin
A nice and simple white rotated tile pattern.
Source Another One
A seamless texture traced from an image on opengameart.org shared by Scouser.
Source Firkin
Prismatic Abstract Line Art Pattern Background
Source GDJ
The tile this is based on can be had by selecting the rectangle in Inkscape and using shift+alt+i
Source Firkin
From a drawing in 'Uit de geschiedenis der Heilige Stede te Amsterdam', Yohannes Sterck, 1898.
Source Firkin
Inspired by the B&O Play, I had to make this pattern.
Source Atle Mo
Some more diagonal lines and noise, because you know you want it.
Source Atle Mo
The file was named striped lens, but hey – Translucent Fibres works too.
Source Angelica
A free seamless background texture of "timber wall" (colored in dark brown).
Source V. Hartikainen
Sort of like the Photoshop transparent background, but better!
Source Alex Parker
Prismatic Snowflakes Pattern 2 No Background
Source GDJ
emixed from a JPG that was uploaded to Pixabay by Kyotime
Source Firkin
A textured orange background pattern with vertical stripes.
Source V. Hartikainen
Prismatic Geometric Tessellation Pattern No Background
Source GDJ
Derived from a corner decoration itself found as a jpg on Pixabay.
Source Firkin