Undo/Redo

Undo snapshot location

Specifies whether to store undo snapshots on disk or in RAM. RAM provides higher performance but you may run out of memory fairly quickly with large images.

Undo buffer snapshot format

When saving undo snapshots to disk, you can choose to use a compressed PNG format or uncompressed Raw Bitmap format. The PNG format saves disk space but uses more CPU, while Raw Bitmap uses more disk space with less CPU resources.

With modern SSDs, the highly compressible Raw Bitmap format is preferred since the SSD controller will be able to write it even faster than the base file size due to hardware compression. You can click the "Benchmark" button to see which format is faster for your system.

Maximum number of history items to show

This controls how many items appear in the History menu. This does not limit the number of undo steps.