The issue was caused by render result identifier only consist of scene name, which could indeed cause conflicts. On the one hand, there are quite some areas in Blender where we need identifier to be unique to properly address things. Usually this is required for sub-data of IDs, like bones. On another hand, it's not that hard to support this particular case and avoid possible frustration. The idea is, we add library name to render identifier for linked scenes. We use library name and not pointer so we preserve render results through undo stack. Reviewers: campbellbarton, mont29, brecht Reviewed By: mont29 Differential Revision: https://developer.blender.org/D2836