The Notebook & Inventory tabs in Projects have been merged into one, unified section. In the new unified listing, entries & entities can be listed together in the same folder (or root level of a project):
Project permissions will not be affected, as we are just changing the way in which project items are organized (but not changing anything about the project itself).
For existing projects, the two Notebook & Inventory tabs will be converted into two Notebook & Inventory folders, with all relevant items from those sections in the relevant folder:
The Create menus from each section will also be merged into one menu. The menu will look slightly different, and some of the options have been grouped together, however all of the relevant options from the old two sections will be present. Note that this Create menu is similar to the Global Create menu you can use from the sidebar, so the menu should still look & feel familiar.