Hi Pilou, well each time you run the command it will make a record of the previous objects in the undo stack.

However, those records are internally compressed (like zipped) to reduce their memory consumption, and also once you exceed a certain amount of memory used by the undo stack (set in moi.ini in the [Undo] section with the MaxMemorySizeMB= setting, default is 20 MB) the older undo records will automatically be purged to free up memory.

It will keep a minimum number of undo steps though before purging any of them, the default is a minimum of 10 steps.

So it's not likely to create a problem for you unless you have such a highly detailed model that it fills up a huge amount of memory just with the minimum 10 undo steps.

- Michael