From an image on opengameart.org shared by rubberduck.
Source Firkin
Can never have too many knitting patterns, especially as nice as this.
Source Victoria Spahn
A light gray fabric pattern with faded vertical stripes.
Source V. Hartikainen
Seamless pattern inspired by a drawing on Pixabay. To get the tile this is formed from, select the rectangle in Inkscape and use shift-alt-i.
Source Firkin
Dark squares with some virus-looking dots in the grid.
Source Hugo Loning
I have no idea how to describe this one, but it’s light and delicate.
Source JBasoo
Sometimes you just need the simplest thing.
Source Fabricio
Background Wall, Art Abstract, Blue Well & CC0 texture.
Source Ractapopulous
This was formed by distorting an image of a background on Pixabay.
Source Firkin
Prismatic Abstract Geometric Background 4
Source GDJ
Background Wall, Art Abstract, Star Well & CC0 texture.
Source Ractapopulous
A seamless dark leather-like background texture with diagonal lines that look like stitches.
Source V. Hartikainen
This background pattern contains a seamless texture of bark. It's not very realistic, but I think it looks quite nice.
Source V. Hartikainen
Oh yes, it happened! A pattern in full color.
Source Atle Mo
Prismatic Abstract Geometric Background 4
Source GDJ
Alternative colour scheme for the original floral pattern.
Source Firkin
Submitted by DomainsInfo – wtf, right? But hey, a free pattern.
Source DomainsInfo
This is the remix of an OCAL clipart called "Art Nouveau ornament" uploaded by "microcosme".Thanks.This is a seamless pattern of an Art Nouveau ornament.
Source Yamachem
Remixed from a raster on Pixabay, that was uploaded by ArtsyBee.
Source Firkin
Pass parameters to the URL or edit the source code variables to configure the graph paper for the division desired.
Source JayNick
Zerro CC tillable texture of stones photographed and made by me. CC0
Source Sojan Janso
The tile this is based on can be retrieved by selecting the rectangle in Inkscape and using shift+alt+i.
Source Firkin