Background pattern 235 #2255
 Yellow  CC 0

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

Source Firkin

 More Textures
Starting Diamond Shape@2X #138
 Light  CC 0

Simple blue and line to mix.

Source SliverKnight

Sine wave background 2 #1734
 Dark  CC 0

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

Source Firkin

Broken Noise@2X #365
 Dark  CC BY-SA 3.0

Beautiful dark noise pattern with some dust and grunge.

Source Vincent Klaiber

Decorative divider 252 #2065
 Dark  CC 0

Remix from a drawing in 'Ostatnie chwile powstania styczniowego', Zygmunt Sulima, 1887.

Source Firkin

Triangular Psychosis 3 #235
 Noise  CC 0

A colorful triangular background, variation 3.

Source GDJ

Background pattern 41 #262
 Fabric  CC 0

A seamless pattern the starting point for which was a 'light rays' rendering in Paint.net.

Source Firkin

Prismatic Hypnotic Pattern 2 No Background@2X #574
 Noise  CC 0

Prismatic Hypnotic Pattern 2 No Background

Source GDJ