A background of randomly colored triangles - followed a tutorial by Espermaschine here: http://gimp-science-labs.blogspot.de/2016/05/filtered-triangles-background.html (without the filtering, but with an updated Inkscape color randomize extension (thank you, Jabier!)).
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Triangle Background free icon was designed by Moini for icons Png and presented to its users.
Moini
1/17/2018