Hi Martin,

> The following seems to be the case if a face is selected for extrusion: - <...>

Yes, unfortunately that's just a limitation on how the history mechanism currently works.

The history function is only able to work when all the inputs that went into the operation are able to be found in the current model.

In your case here the face that you selected as the input into the extrusion isn't present after doing the auto-booleaned extrusion, it's eliminated during the boolean operation. If you check the "Keep separate" option before you click "Set path" you should then get a result that will be able to update as you were looking for but the pieces will all be separate instead of booleaned together.

In the future I want to overhaul the history mechanism to keep a kind of parallel separate database of all previous objects in it so that operations like you're trying to do will work with history. That will involve a major effort though.

- Michael

Hi Michael.

It's not a big deal for me, because by selecting the top edges of the first solid rather than just its top face, this allows for the second solid to be updated either by resizing the rectangle or reshaping the extrude path curve. It was only when I found that selecting a face acted differently that I wondered if something needed a tweak.

Cheers.

Martin.