As for the object undo system, there is no memory limit for this at the moment, but only a (small) step limit. But an undo step for image drawing only stores a copy of the part of the image which was painted over, and painting over a whole huge base map does not occur in regular use.
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As for the object undo system, there is no memory limit for this at the moment, but only a (small) step limit. But an undo step for image drawing only stores a copy of the part of the image which was painted over, and painting over a whole huge base map does not occur in regular use.