The tile this is based on can be had by selecting the rectangle in Inkscape and using shift+alt+i
Source Firkin
And some more testing, this time with Seamless Studio. It’s Robots FFS!
Source Seamless Studio
Alternative colour scheme. 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
A background formed from an image of an old tile on the New York Metropolitan Museum of Art website. To get the base tile, select the rectangle in Inkscape and use shift-alt-i.
Source Firkin
Prismatic Chevrons Pattern 5 With Background
Source GDJ
It’s big, it’s gradient—and it’s square.
Source Brankic1979
Number 1 in a series of 5 beautiful patterns. Can be found in colors on the submitter’s website.
Source Janos Koos
Seamless pattern formed from a tile that can be had by selecting the rectangle in Inkscape and using shift-alt-i.
Source Firkin
Square design drawn in Paint.net and vectorized in Vector Magic.
Source Firkin
A seamless pattern the starting point for which was a 'colour modulo' texture in Paint.net.
Source Firkin
Prismatic Abstract Background Design
Source GDJ
A colourful background drawn originally in paint.net and vectorised in Vector Magic.
Source Firkin
From a drawing in 'Cassell's Library of English Literature', Henry Morley, 1883.
Source Firkin
A seamless chequerboard pattern formed from a tile that can be had in Inkscape by selecting the rectangle and using shift+alt+i. Alternative colour scheme.
Source Firkin
Vertical lines with a bumpy, yet crisp, feel to it.
Source Raasa
Embossed lines and squares with subtle highlights.
Source Alex Parker
Dare I call this a «flat pattern»? Probably not.
Source Dax Kieran
The tile this is based on can be retrieved by selecting the rectangle in Inkscape and using shift+alt+i.
Source Firkin
Not strictly seamless in that opposite edges are not identical. But they do marry up to make an interesting pattern
Source Firkin
From a design in 'Storia del Palazzo Vecchio in Firenze', Aurelio Gotti, 1889.
Source Firkin
A seamless pattern the starting point for which was a 'rainbow twist' texture in Paint.net.
Source Firkin
From a drawing in 'Line and form', Walter Crane, 1914.
Source Firkin
Not the most creative name, but it’s a good all-purpose light background.
Source Dmitry