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
A dark one with geometric shapes and dotted lines.
Source Mohawk Studios
Zero CC tileable bark texture, photographed and made by me. CC0
Source Sojan Janso
I know there is one here already, but this is sexy!
Source Gjermund Gustavsen
Submitted in a cream color, but you know how I like it.
Source Devin Holmes
A lovely light gray pattern with stripes and a dash of noise.
Source V. Hartikainen
Super detailed 16×16 tile that forms a beautiful pattern of straws.
Source Pavel
Seamless , tileable CC-0 texture. Created by my own, feel free to use wherever you want!
Source Linolafett
One more sharp little tile for you. Subtle circles this time.
Source Blunia
Alternative colour scheme. Not a pattern for fabrics, but one produced from a jpg of a stack of fabric items that was posted on Pixabay. The tile that this is based on can be had by selecting the rectangle in Inkscape and using shift+alt+i.
Source Firkin
A pale yellow background pattern with vertical stripes. The stripes are partially faded. I think this background image turned out pretty well, especially those faded stripes.
Source V. Hartikainen
Zero CC tileable pine bark texture, photographed and made by me. CC0
Source Sojan Janso
Remixed from a raster on Pixabay that was uploaded by ArtsyBee.
Source Firkin
High detail stone wall with minor cracks and specks.
Source Projecteightyfive
The image depicts a seamless pattern made using a bird's face.
Source Yamachem
Adapted from an image that was uploaded to Pixabay by Anerma.
Source Firkin
You may use it as is, or modify it as you like.
Source V. Hartikainen
Prismatic Groovy Concentric Background 4 No Black
Source GDJ
To get the tile this is based on select the rectangle in Inkscape and use shift+alt+i.
Source Firkin