I noticed that when I rename a .css file in the Project tab of pinegrow pinegrow creates a copy of the .css file and leaves the old one in the project folder. In addition to that, renaming does not adjust links to the .css file in other files to reflect changes to the name of the .css file.
When using the Stylesheet Manger links to the .css are changed to reflect changes to the name of the .css file, but pinegrow still creates a copy of the .css file. The latter might be wanted behavior, but I do not see the reason behind keeping the old file when renaming.
My system information: Running pinegrow 5.94 on MacOS Catalina 10.15.3.