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
Because I love dark patterns, here is Brushed Alum in a dark coating.
Source Tim Ward
A seamless pattern the starting point for which was a 'colour modulo' texture in Paint.net.
Source Firkin
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 new one called white wall, not by me this time.
Source Yuji Honzawa
Looks like an old wall. I guess that’s it then?
Source Viahorizon
From a drawing in 'Art Embroidery', M.S. Lockwood and E. Glaister, 1878.
Source Firkin
A pattern derived from repeating unit cells each derived from part of a fractal rendering in paint.net.
Source Firkin
From a drawing in 'Navigations de Alouys de Cademoste.-La Navigation du Capitaine Pierre Sintre', Alvise da ca da Mosto, 1895.
Source Firkin
A pattern formed from a squared tile. The tile can be accessed in Inkscape by selecting the rectangle and using shift-alt-i.
Source Firkin
This is the remix of "Strawberry Pattern Background" uploaded by "GDJ". Thanks. I realigned strawberries so as to get seamless and changed the BG color.
Source Yamachem
Background pattern originally a PNG drawn in Paint.net
Source Firkin
And some more testing, this time with Seamless Studio. It’s Robots FFS!
Source Seamless Studio
From a drawing in 'At home', J. Sowerby, J. Crane and T. Frederick, 1881.
Source Firkin
From a tile that can be had by selecting the rectangle in Inkscape and using shift+alt+i.
Source Firkin
Some more diagonal lines and noise, because you know you want it.
Source Atle Mo
To get the tile this is based on, select the rectangle in Inkscape and use shift+alt+i
Source Firkin
A repeating background of thick textured paper. Actually, it turned out to look like something between a paper and fabric.
Source V. Hartikainen
Background Wall, Art Abstract, Block Well & CC0 texture.
Source Ractapopulous
Zero CC asphalt, pavement, texture, photographed and made by me. CC0 WARNING I FOUND A SEAM ON THIS TEXTURE
Source Sojan Janso
A web texture of brown canvas. Will look great, when used in dark web designs.
Source V. Hartikainen