Ah - thanks. I’ve been doing that for ages, but until you pointed me at it I didn’t notice that the library is given in the window title. I was confused as you have to then “Select working library” before you can save updates to the component.
I think it would be more intuitive if it assumed you wanted to edit the component in the current library, but still allowed a different library to be selected. However, it won’t cause me problems any more now that I know.
Ah - in case it helps anyone else, since posting the above I’ve realised I can use the “Update current component in current library” button rather than finding the library and then saving to it.