Help with node tool 90 degree handle alignment

[Marie Elisabeth]

I've tried searching but haven't found what I'm looking for. I work in Publisher 2 on Win 11, mostly in Designer persona for this.

After creating a curve with the pen tool I want to use the node tool to make sure certain corners are a true 90 degrees. There is a red 90 degree mark that pops up when rotating the handle of a sharp node. My problem is that sometime this does not happen. 

I have tried different options with the snap options in node tool and options for snapping. Can someone please help me figure out how to make it show? (Yes I can use a workaround to snap to other lines or rectangles but I shouldn't have to.)

[thomaso]

It appears to need the button "Perform construction snapping" in the Context Toolbar activated. Having all snapping options in the snapping menu does not seem to be enough.