I create a symbol LM 339 using imported spice subcircuit
This can be used in the current schematic and works great
How do I save this symbol so if I open a new schematic , it can be selected from the left hand symbol IP menu . In summary a method to add to a custom library so I can access this for simulation
If you click on the folder icon in the top left corner of the Symbol & IP Browser, it will allow you to select a folder to add to the browser. Pick the folder where your LM339 model is stored, and it will appear.
I tried your steps above with a few different models from various vendors (Analog, TI, Wurth) and they did not show up in the tree. When I right click on a folder in the tree and click on “Edit user-supplied directories” I can see the folders, but there are no models.
To refresh after copying new symbol files into that folder, you have to close and rerun Qspice. It seems Qspice only refresh its Symbol & IP Browser when its launch.