Diamond pattern 2 (colour 6) #2261
 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
Snowflake pattern remix #156
 Dark  CC 0

The base gradient edited so now more details are rendered.

Source Lazur URH

Robots #125
 Dark  CC BY-SA 3.0

And some more testing, this time with Seamless Studio. It’s Robots FFS!

Source Seamless Studio

Polaroid@2X #188
 Wall  CC BY-SA 3.0

Smooth Polaroid pattern with a light blue tint.

Source Daniel Beaton

Prismatic Dots Background 3@2X #506
 Noise  CC 0

Prismatic Dots Background 3

Source GDJ

Felt #300
 Wall  CC BY-SA 3.0

Got some felt in my mailbox today, so I scanned it for you to use.

Source Atle Mo

fishnet 01 #2475
 Grid  CC 0

The image depicts a seamless pattern of a fishnet with a plenty of fish.It may be a lucky charm for fishermen.

Source Yamachem

Background pattern 195 #2587
 Grid  CC 0

Inspired by a pattern I saw in a 19th century book. This seamless pattern was created from a square tile. To get the tile, select the pattern in Inkscape and use shift+alt+i.

Source Firkin

Part of Bayeux Tapestry 2 #2451
 Noise  CC 0

From a drawing in 'Les Chroniqueurs de l'Histoire de France depuis les origines jusqu'au XVIe siècle', Henriette Witt, 1884.

Source Firkin

Retro Squares Background 9 #399
 Dark  CC 0

Retro Squares Background 9

Source GDJ

Carbon Fiber Big #326
 Carbon  CC BY-SA 3.0

Bigger is better, right? So here you have some large carbon fiber.

Source Factorio.us Collective

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

Lego background #266
 Noise  CC 0

Background formed from the iconic plastic construction bricks that gave me endless hours of fun when I was a lad.

Source Firkin

Flowery pattern 4 #2328
 Colorful  CC 0

Remixed from a vector adapted from a jpg on Pixabay. The tile this is constructed from can be had by selecting the rectangle in Inkscape and using shift-alt-i.

Source Firkin