9a622f18ac
More problems with Undo and Render Slots (Image editor) - Undo storage for operator is now back, but only when new buffers were added (not when viewing existing) - A real bug: On undo/redo, the stored buffers were never retrieved, but always freed entirely. Note however that when you undo back to a state before you rendered (or added slots), the render buffers that didn't exist back then also get freed. A redo doesn't bring it back.