Remixed from a design seen on Pixabay. The basic tile can be had by selecting the rectangle in Inkscape and using shift+alt+i
Source Firkin
Design drawn in Paint.net, vectorised using Vector Magic and finished in Inkscape.
Source Firkin
Dark, square, clean and tidy. What more can you ask for?
Source Jaromír Kavan
Prismatic Snowflakes Pattern No Background
Source GDJ
The unit cell for this seamless pattern can be had in Inkscape by selecting the rectangle and using shift+alt+i.
Source Firkin
To get the tile this is formed from select the rectangle in Inkscape and use shift+alt+i.
Source Firkin
One of the few full-color patterns here, but this one was just too good to pass up.
Source Alexey Usoltsev
Just like your old suit, all striped and smooth.
Source Alex Berkowitz
Retro Circles Background 5 No Black
Source GDJ
Light gray pattern with an almost wall tile-like appearance.
Source Markus Tinner
Remixed from a drawing in 'Hungary. A guide book. By several authors', 1890.
Source Firkin
Prismatic Rounded Squares Grid 4 No Background
Source GDJ
And some more testing, this time with Seamless Studio. It’s Robots FFS!
Source Seamless Studio
This is a remix of "geometrical pattern 01".
Source Yamachem
A light brushed aluminum pattern for your pleasure.
Source Tim Ward
I guess this is inspired by the city of Ravenna in Italy and its stone walls.
Source Sentel
Remixed from a drawing in 'A Girl in Ten Thousand', Elizabeth Meade, 1896.
Source Firkin
Prismatic Polka Dots Mark II No Background
Source GDJ
A seamless pattern formed from a square tile. The tile can be retrieved by selecting the rectangle in Inkscape and using shift-alt-I.
Source Firkin
Prismatic Abstract Background Design
Source GDJ
This beige background pattern resembles a concrete wall with engravings or something similar to it.
Source V. Hartikainen
Dark squares with some virus-looking dots in the grid.
Source Hugo Loning