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This problem has persisted for a long time. On the image I have attached you can see that there is a vertical white line to left of the red square. When exporting the white line is still there – the only way to avoid it is to have the graphics stretched beyond the artboard before exporting.
Why has this never been fixed??
Eduardo C. Beer-Svendsen commented
Correction, well, the white line is actually 100% transparent it seems like.