I don’t know if this is the place to post bugs, but I’ve been having this issue lately. I think it started after switching to Revit 2019, but I’m not sure. I wonder if anyone else experienced it and knows what’s causing it.
Basically what happens is whenever I create a new node or copy an existing one (but mostly when I copy an existing one), when I deselect the newly created node(s) then re-select it and move it, any previously selected node(s) will jump to the mouse position at that moment, and many times it ends up bringing the node all the way from the other side of the script and places it right on top/under the new node.
And what’s worse, it’s not undo-able. I’ve uploaded a recording below.