A simple example on using clones. You can generate a nice base for a pattern fill quickly with it.
Source Lazur URH
Prismatic Curved Diamond Pattern 3 No Background
Source GDJ
Prismatic Groovy Concentric Background No Black
Source GDJ
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
From a tile that can be had by selecting the rectangle in Inkscape and using shift+alt+i.
Source Firkin
A background pattern inspired by designs seen in 'Burghley. The Life of William Cecil', William Charlton, 1857.
Source Firkin
To get the tile this is based on select the rectangle in Inkscape and use shift+alt+i.
Source Firkin
You can never get enough of these tiny pixel patterns with sharp lines.
Source Designova
Just what the name says, paper fibers. Always good to have.
Source Heliodor jalba
Abstract Ellipses Background Grayscale
Source GDJ
Derived from an image that was uploaded to Pixabay by Darkmoon1968
Source Firkin
A web texture of brown canvas. Will look great, when used in dark web designs.
Source V. Hartikainen
And some more testing, this time with Seamless Studio. It’s Robots FFS!
Source Seamless Studio
This was formed by distorting an image of a background on Pixabay.
Source Firkin
A dark metal plate with an embossed grid pattern and a bit of rust. Here's a dark metal plate texture for use as a tiled background on web pages.
Source V. Hartikainen
From a drawing in 'Sun Pictures of the Norfolk Broads', Ernest Suffling, 1892.
Source Firkin
The image depicts a seamless pattern of the design which includes a stylized lotus and a stylized crane.I referred to the original image in a book which is into public domain.
Source Yamachem
Prismatic Abstract Line Art Pattern Background
Source GDJ
Prismatic Isometric Cube Extra Pattern No Background
Source GDJ
All good things come in threes, so I give you the third in my little concrete wall series.
Source Atle Mo
Dark, square, clean and tidy. What more can you ask for?
Source Jaromír Kavan