I took the liberty of using Dmitry’s pattern and made a version without perforation.
Source Atle Mo
Prismatic Abstract Line Art Pattern Background
Source GDJ
The image is a remix of "edo pattern-samekomon".I changed the color of dots from black to white and added BG in light-yellow.
Source Yamachem
The basic shapes never get old. Simple triangle pattern.
Source Atle Mo
Seamless , tileable CC-0 texture. Created by my own, feel free to use wherever you want!
Source Linolafett
Your eyes can trip a bit from looking at this – use it wisely.
Source Michal Chovanec
Sometimes simple really is what you need, and this could fit you well.
Source Factorio.us Collective
A seamless texture traced from an image on opengameart.org shared by Scouser.
Source Firkin
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
This was formed by distorting an image of a background on Pixabay.
Source Firkin
Remixed from a raster on Pixabay, that was uploaded by ArtsyBee.
Source Firkin
Inspired by a drawing in 'Kulturgeschichte', Freidrich Hellwald, 1896.
Source Firkin
It has waves, so make sure you don’t get sea sickness.
Source CoolPatterns
More bright luxury. This is a bit larger than fancy deboss, and with a bit more noise.
Source Viszt Péter
This background texture resembles stone. It may be used as a background on web pages or on some of their html elements (header, borders, menu bar, etc.). Just modify it for your needs.
Source V. Hartikainen
As far as fabric patterns goes, this is quite crisp.
Source Heliodor Jalba
This light blue background pattern is quite pleasing to the eye, it consists of a tiny rough grid pattern, which is seamless by design. That's it, if you like the color, you can use this seamless pattern in a web design without making any further modifications to it.
Source V. Hartikainen
To get the tile this is based on, select the rectangle in Inkscape and use shift+alt+i.
Source Firkin
Horizontal and vertical lines on a light gray background.
Source Adam Anlauf
The starting point for this was drawn on the web site steamcoded.org/PolyskelionMaker.svg
Source Firkin
A rusty grunge background for websites. Feel free to use it in your site's theme.
Source V. Hartikainen
Zerro CC tillable texture of stones photographed and made by me. CC0
Source Sojan Janso
White handmade paper pattern with small bumps.
Source Marquis