Through trial and error I have found what causes this issue (at least one cause.- maybe there are more).
The problem for me was caused by the combination of two things:
Having the "Blur" option switched on for one of the groups in the Icon Composer file
For that group, having at least one SVG sitting near the edge of the canvas. I'm not sure exactly where the line is, but if your SVG is in the middle, it doesn't trigger the issue - even with Blur turned on. It only shows up once your SVG is near the edge.
So for me, the fix was to turn off the blur setting on the group that had an SVG near the edge.
Topic:
Developer Tools & Services
SubTopic:
Instruments
Tags: