Background pattern 339 (colour) #1708
 Yellow  CC 0

The tile this is based on can be had by selecting the rectangle in Inkscape and using shift+alt+i

Source Firkin

 More Textures
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

Colorful Geometric Pattern Background #231
 Noise  CC 0

PDP

Source GDJ

Axiom Pattern@2X #331
 Grid  CC BY-SA 3.0

Not even 1kb, but very stylish. Gray thin lines.

Source Struck Axiom

Prismatic Curved Diamond Pattern No Background #536
 Diamond  CC 0

Prismatic Curved Diamond Pattern No Background

Source GDJ

Background pattern 6 #226
 Noise  CC 0

A pattern derived from part of a fractal rendering in Paint.net.

Source Firkin

White Sand #19
 Light  CC BY-SA 3.0

Same as gray sand but lighter. A sandy pattern with small light dots, and some angled strokes.

Source Atle Mo

Floral pattern 7 (colour 3) #2289
 Pink  CC 0

Utilising some flowers from Almeidah. To get the unit tile, select the rectangle in Inkscape and use shift-alt-i.

Source Firkin

Background pattern 223 (colour 2) #2352
 Blue  CC 0

Seamless pattern formed from a tile that can be had by selecting the rectangle in Inkscape and using shift-alt-i.

Source Firkin

Background pattern 214 (colour 6) #2372
 Colorful  CC 0

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

Groovepaper #577
 Paper  CC BY-SA 3.0

With a name like this, it has to be hot. Diagonal lines in light shades.

Source Isaac

Background pattern 10 #216
 Noise  CC 0

A pattern drawn in Paint.net and vectorized in Vector Magic.

Source Firkin

Prismatic Floral Background No Black #475
 Light  CC 0

Prismatic Floral Background No Black

Source GDJ

Background pattern 227 (colour 4) #2311
 Green  CC 0

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

Starring #585
 Dark  CC BY-SA 3.0

If you need stars, this is the one to get.

Source Agus Riyadi