Remixed from a raster on Pixabay, that was uploaded by ArtsyBee.
Source Firkin
To get the tile this is based on, select the rectangle in Inkscape and use shift-alt-i.
Source Firkin
Prismatic Abstract Background Design No Black
Source GDJ
A seamless pattern the starting point for which was a 'rainbow twist' texture in Paint.net.
Source Firkin
A beautiful dark padded pattern, like an old classic sofa.
Source Chris Baldie
To get the tile this is based on select the rectangle in Inkscape and use shift+alt+i.
Source Firkin
Background Wall, Art Abstract, Block Well & CC0 texture.
Source Ractapopulous
The file was named striped lens, but hey – Translucent Fibres works too.
Source Angelica
A pattern drawn in Paint.net and vectorized in Inkscape.
Source Firkin
Pattern formed from simple shapes. Black version.
Source Firkin
A seamless background drawn in Paint.net and vectorised with Vector Magic. The starting point was a photograph of drinking straws from Pixabay.
Source Firkin
Drawn in Paint.net and vectorised in Vector Magic.
Source Firkin
This background pattern contains a seamless texture of bark. It's not very realistic, but I think it looks quite nice.
Source V. Hartikainen
Remixed from a drawing in 'Analecta Eboracensia', Thomas Widdrington, 1897.
Source Firkin
Derived from an image that was uploaded to Pixabay by darkmoon1968
Source Firkin
Prismatic Basic Pattern 2 No Background
Source GDJ
Sometimes simple really is what you need, and this could fit you well.
Source Factorio.us Collective