Removing devices and leaving lose Wire Nodes around without wires attached to it crashes WM when you try to save a project.
Took me a while to realise and overcome this by making sure you dont leave loose wire nodes after device removal. (either delete nodes first, then the rest)
Oops – this is a bug in 2.3.6.3 that is fixed in more recent versions. I will issue a bugfix release for this and several other issues still in 2.3.6.3 next week.
Really? I could swear it also happened on a 2.9 developer version because I remember I switched back from 2.9dev to the official 2.3 version and it still happened. (Unless its a flaw that transfers with the project file?)