Thanks for reaching out to us!
We will be introducing a Canvas Color tool soon to make this task slightly easier, however you can achieve it right now by:
– Opening up the Effects tab > Sketch tool (towards the end of the tab)
– “Picking” the color by clicking the tool’s color rectangle and then on the photo
– Painting over your entire canvas (increasing the brush size will make this a quick task)
Let us know if you have any other questions!
Regards – The Ribbet Team