Background pattern 215 (colour 3) #2369
 Pink  CC 0

A grid of squares with green colours. Since the colours are randomly distributed it is automatically seamless.

Source Firkin

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Background pattern 223 (colour 5) #2349
 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 273 #2042
 Dark  CC 0

Remixed from a design seen in 'Burghley. The Life of William Cecil', William Charlton, 1857.

Source Firkin

Leafy design 18 (colour)@2XaFloral design 96 (colour) #1787
 Green  CC 0

From a drawing in 'Art Embroidery', M.S. Lockwood and E. Glaister, 1878.

Source Firkin

Colorful Floral Background 3 #483
 Dark  CC 0

Colorful Floral Background 3

Source GDJ

Real Carbon Fiber #286
 Carbon  CC BY-SA 3.0

Carbon fiber is never out of fashion, so here is one more style for you.

Source Alfred Lee

Prismatic Dots Background 2@2X #504
 Noise  CC 0

Prismatic Dots Background 2

Source GDJ

Spirals pattern #1994
 Colorful  CC 0

Uses spirals from Pixabay. To get the basic tile select the rectangle in Inkscape and use shift+alt+i

Source Firkin

Vintage tile background (colour 3) #2246
 Green  CC 0

A background formed from an image of an old tile on the New York Metropolitan Museum of Art website. To get the base tile, select the rectangle in Inkscape and use shift-alt-i.

Source Firkin

Retro Squares Background 9 #399
 Dark  CC 0

Retro Squares Background 9

Source GDJ

Prismatic Dots Background 8@2X #516
 Noise  CC 0

Prismatic Dots Background 8

Source GDJ