Layer has a sheen over the thumbnail, how did this happen?

[Blighty]

(11-21-2019, 09:39 PM)marigolden Wrote: I was going along creating layers for each pasted dot

It would be much easier if you made a brush out of one of your dots.

From your image I can't tell the size of the dot, how much transparency it has, etc. Could you make an xcf file containing just one layer (eg the layer named small). This can be made into a brush. Then it is just a single click to add a dot.