This list shows the projects you have been invited to and which you have added to the list. You can search for all projects created through "Search for projects" (found in the menu on the left) and add desired projects to the quick list by clicking the arrow to the left of the project name and then on "Add to the quick list". The idea behind the list is that you should be able to manage and add to the projects you want in the list, eg those projects that are current and that you work with most.
When switching to a new project module, the list will be empty and you will therefore need to look up and add the projects you want in your quick list. When searching for projects, all projects will appear and you can add all projects to the list. In order to open a project that you have added to the list, you must either be invited to it (applies to rights-managed projects) or it must be open to everyone (not rights-managed).