Picking up colors too similar to the window background makes them difficult to know they're been saved in the palette at all. See screenshot for an extreme case: there are two saved colors there.
I suggest having a light 2px border around them to make them stand out.
Thanks for the report, it's fixed in 74e2bc0237643b05244967b73b53e22ad4484b74. While the idea of a border is good, I solved it by adding a shadow to the color item, which is less intrusive.
Picking up colors too similar to the window background makes them difficult to know they're been saved in the palette at all. See screenshot for an extreme case: there are two saved colors there. I suggest having a light
2px
border around them to make them stand out.