When tool-bar is activated the filenames tab bar is hidden at start up and I have to go into settings and turn tabs on and off again under "Core Packages". Tabs work fine and appear on startup when the tool-bar is disabled.
Update: Apologies, my initial report was a little misleading. I am using the project-manager package. More accurately, tabs are displayed on start up but disappear below the tool-bar when I open a project from the project-manager list. Not sure which package is causing the problem but thought I'd report it anyway.