Comment 14 for bug 290870

It is easy to reproduce all the described issues in 0.48 (Linux)

1. Go into Bezier drawing mode
2. click (producing a cusp node A without handles)
3. click-drag, and while dragging, hit shift, breaking the smooth node (producing a cusp node B with handles)
4. click back on the first node A (closing the curve, leaving A a cusp node without handles)

This produces a two-segment closed curve of which none of the segments are selectable. Ctrl-clicking on the first node A does not change its node type, just the node symbol.

Doing anything with node A always makes it become a cusp without tangents again.
Even when you shift-drag tangents out of node A, and then ctrl-click to change node type, it'll fall back to cusp without tangents.

The described mis-behavior seems to vanish when three nodes are involved (repeating step 3 above). You get a three-segment curve that so far seems to work as desired.

Update: the recipe doesn't work always, but frequently :(