Occurrence
When you try to digitize or draw an object in a layer, it is snapping back to a straight line along an invisible edge. Or certain tools may produce output like this with data following an invisible boundary box.
Solution
This is caused when a table has explicit bounds (typically non-earth projections, as these always have explicit bounds on the table).
To increase the bounds, go to HOME>Tool Extensions>Registered there is the CoordSys Bounds Manager tool. This allows you to automatically increase the bounds by a buffer precentage, to give more room to digitize outside the existing data.
Simply open this tool, then click Optimize CoordSys Bounds. Then click Save Table As.. with CoordSys Bounds.
There is a similar tool in DISCOVER>Tables>Modify Bounds, but it has less options and not as user friendly, as it requires you to manually type in coordinates.