Just to prove my point, here is a slightly modified dark version.
Source Atle Mo
White fabric looking texture with some nice random wave features.
Source Hendrik Lammers
Number 5 in a series of 5 beautiful patterns. Can be found in colors on the submitter’s website.
Source Janos Koos
The tile this is based on can be had by selecting the rectangle in Inkscape and using shift+alt+i
Source Firkin
Dark, lines, noise, tactile. You get the drift.
Source Anatoli Nicolae
More in the paper realm, this time with fibers.
Source Jorge Fuentes
You know you can’t get enough of these linen-fabric-y patterns.
Source James Basoo
Classy golf-pants pattern, or crossed stripes if you will.
Source Will Monson
If you want png files of this u can download them here : viscious-speed.deviantart.com/gallery/27635117
Source Viscious-Speed
This was formed by distorting an image of a background on Pixabay.
Source Firkin
CC0 and a seamless pattern from a tile drawn in Paint.net .
Source SliverKnight
A seamless pattern formed from a tile made from ornament 22. To get the tile, select the rectangle in Inkscape and use shift+alt+i.
Source Firkin
Classic vertical lines, in all its subtlety.
Source Cody L
New paper pattern with a slightly organic feel to it, using some thin threads.
Source Atle Mo
From a drawing in 'Les Chroniqueurs de l'Histoire de France depuis les origines jusqu'au XVIe siècle', Henriette Witt, 1884.
Source Firkin
A pattern formed from a photograph of a 16th century ceramic tile.
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
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
From a drawing in 'Art Embroidery', M.S. Lockwood and E. Glaister, 1878.
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. Version with black background.
Source Firkin
Remixed from a drawing in 'Works. Popular edition', John Ruskin, 1886.
Source Firkin
From a drawing in 'At home', J. Sowerby, J. Crane and T. Frederick, 1881.
Source Firkin
Seamless pattern the tile for which can be had by using shift-alt-I on the selected rectangle in Inkscape.
Source Firkin