Background pattern 249 #2179
 Blue  CC 0

To get the tile this is made up from select the rectangle in Inkscape and use shift+alt+i.

Source Firkin

 More Textures
Seamless 3D Isometric Tessellation Pattern 2 #147
 Light  CC 0

A seamless pattern that includes the original tile (go to Objects / Pattern / Pattern To Objects in Inkscape's menu to extract it).

Source GDJ

Abstract Ellipses Background Grayscale #378
 Dark  CC 0

Abstract Ellipses Background Grayscale

Source GDJ

Kaleidoscope Prismatic Abstract No Background #387
 Noise  CC 0

Kaleidoscope Prismatic Abstract No Background

Source GDJ

Background pattern 112 #263
 Fabric  CC 0

A seamless pattern with a unit cell drawn as a bitmap in Paint.net and vectorized in Vector Magic.

Source Firkin

Background pattern 309 (colour 3) #1864
 Red  CC 0

Design drawn in Paint.net, vectorised using Vector Magic and finished in Inkscape.

Source Firkin

Prismatic Hypnotic Pattern No Background@2X #572
 Noise  CC 0

Prismatic Hypnotic Pattern No Background

Source GDJ

Fabric pattern 3 #2387
 Fabric  CC 0

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

“Transparent” Background Pattern #493
 Light  CC 0

An emulated “transparent” background pattern, like that of all kinds of computer graphics software.

Source AdamStanislav

Prismatic Groovy Concentric Background 2 #453
 Noise  CC 0

Prismatic Groovy Concentric Background 2

Source GDJ

Background pattern 203 #2486
 Brown  CC 0

A seamless pattern formed from a square tile. To get the tile, select the rectangle in Inkscape and use shift+alt+i.

Source Firkin