I see I'm not the only person puzzled by the absence of this tool. And I appreciate all of your several posts over the last two years that explain that I should be able to select a node on a curve or on a shape, and then use the "Break Curve action on the context menu."
But darned if I can find anything remotely resembling such a command anyplace on the screen or in the menus. I'm new to AD, but I gather that the "context menu" is supposed to appear immediately above the work space, after I have selected (and used) the node tool to select a node. If that's the context menu, then there simply ain't such a button or action that suggests I can "break curve." In my case , what I see for choices on the screen above the workspace includes just these choices: Corner...Fill...Stroke...(line thickness).. Corner type.. Radius.. Bake corners.
Can you give me a hint as to where to find the "break curve" action? (Affinity Designer 1.5.4 Yosemite OS 10.10.5)