Diamond pattern 2 (colour 3) #2266
 Colorful  CC 0

From a tile that can be had by selecting the rectangle in Inkscape and using shift+alt+i.

Source Firkin

 More Textures
Graphy@2X #351
 Grid  CC BY-SA 3.0

Looks like a technical drawing board: small squares forming a nice grid.

Source We Are Pixel8

Zodiac sign symbol background #1927
 Red  CC 0

Just the symbols of the signs of the zodiac distributed in a chequer board-like pattern

Source Firkin

Background pattern 306 (colour 6) #1878
 Colorful  CC 0

Seamless pattern the tile for which can be had by using shift-alt-I on the selected rectangle in Inkscape.

Source Firkin

Dark Circles@2X #307
 Dark  CC BY-SA 3.0

People seem to enjoy dark patterns, so here is one with some circles.

Source Atle Mo

Background pattern 220 #2360
 Dark  CC 0

A seamless pattern formed from a tile that can be had in Inkscape by selecting the rectangle and using shift+alt+i. Derived from a design in 'Storia del Palazzo Vecchio in Firenze', Aurelio Gotti, 1889.

Source Firkin

Background pattern 250 #2172
 Dark  CC 0

To get the tile this is based on select the rectangle in Inkscape and use shift+alt+i.

Source Firkin

Background pattern 6 #225
 Noise  CC 0

Another fairly simple design drawn in Paint.net and vectorized in Inkscape.

Source Firkin

Prismatic Arrows Background 2 #393
 Light  CC 0

Prismatic Arrows Background 2

Source GDJ

Abstract Stars Geometric Pattern Prismatic No Background #384
 Noise  CC 0

Abstract Stars Geometric Pattern Prismatic No Background

Source GDJ

Parquet flooring pattern (colour 2) #2426
 Green  CC 0

A seamless pattern recreated from an image on Pixabay. It is reminiscent of parquet flooring and is formed from a square tile, which can be recovered in Inkscape by selecting the ungrouped rectangle and using shift-alt-I together.

Source Firkin

Floral pattern 18 #1716
 Dark  CC 0

A pattern formed from repeated instances of corner decoration 8. To get the basic tile select the rectangle in Inkscape and use shift+alt+i

Source Firkin

Prismatic Dots Background 5 #509
 Noise  CC 0

Prismatic Dots Background 5

Source GDJ

Background pattern 235 (colour 3) #2253
 Pink  CC 0

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

Source Firkin

Project Papper #119
 Paper  CC BY-SA 3.0

Light square grid pattern, great for a “DIY projects” sort of website, maybe?

Source Rafael Almeida

Starting Diamond Shape #137
 Light  CC BY-SA 3.0

Simple blue and line to mix.

Source SliverKnight