Dark squares with some virus-looking dots in the grid.
Source Hugo Loning
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
Prismatic Abstract Geometric Background 4
Source GDJ
Just what the name says, paper fibers. Always good to have.
Source Heliodor jalba
This one could be the shirt of a golf player. Angled lines in different thicknesses.
Source Olivier Pineda
Abstract Arbitrary Geometric Background derived from an image on Pixabay.
Source GDJ
Your eyes can trip a bit from looking at this – use it wisely.
Source Michal Chovanec
The original has been presented as black on transparent and stored in the pattern definitions. To retrieve the unit tile select the rectangle in Inkscape and use shift+alt+i
Source Firkin
A version without colours blended together to give a different look.
Source Firkin
A seamless pattern based on a rectangular tile that can be retrieved in Inkscape by selecting the rectangle and using shift-alt-i.
Source Firkin
Sweet and subtle white plaster with hints of noise and grunge.
Source Phil Maurer
Pattern #100! A black classic knit-looking pattern.
Source Factorio.us Collective
This ladies and gentlemen, is texturetastic! Love it.
Source Adam Pickering
Prismatic Floral Background No Black
Source GDJ
From a drawing in 'Bond Slaves. The story of a struggle.', Isabella Varley, 1893.
Source Firkin
Drawn in Paint.net using the kaleidoscope plug-in and vectorised.
Source Firkin
From a drawing in 'Art Embroidery', M.S. Lockwood and E. Glaister, 1878.
Source Firkin
The unit cell for this seamless pattern can be had in Inkscape by selecting the rectangle and using shift+alt+i.
Source Firkin
Prismatic Groovy Concentric Background 2
Source GDJ
Design drawn in Paint.net, vectorised using Vector Magic and finished in Inkscape.
Source Firkin