Thats fine, it is my vacation computer, factorio is basically the only game that will run on it.
I just reported the issue as I had not seen it before, and maybe it was introduced by a new patch.

After changing to 4096 atlas size, I have not been able to replicate the issue, so that seems to fix ...

Another game session had the issue happen to the water, probably easier to debug.
Also see lower left and right of minimap.

Thanks for making a great game.
After playing for a while, various graphical glitches appear in both map mode and main game view.
It seems the glitches start appearing after alt tabbing into chrome showing streams.
They seem to have no impact on gameplay.
The glitches are in consistent locations ...