Painter goes black after a while

[juliankrispel]

After some hours not attending the tab the painter is running in and going black, I found that the painter was painting black HOLY MOLY.

Now why would this be I ask?

My initial suspicion is Chromes goddamn garbage collection.

[ulikk]

I tried to recreate that situation, but it runs for hours without turning black here. I however suspect that the image contexts are getting invalid after the system goes into sleep mode. This should be fixable in the main loop (iterate), by updating "dstContext" inside the loop if it becomes invalid.