More appears only when the window is too narrow for all of them: the tabs that do not fit move into it, starting from the right, and while the open page is one of them More is underlined like an open tab, pointing at it says which page is open and the page is marked in its menu. Widening the window brings the tabs back out, and every page of the project uses the whole width of the window.
Overview tells you what happened since your last visit: what needs you, what changed and where the project is going; Planning is where the project is going, with its plans, In progress or Completed, the most voted first; Rules, called Environment before version 13.2.49.74, holds what agents must always follow on Staging and Production; Activity lists what was done and by whom; Conversations, called Syndication before version 13.2.49.71, whose tooltip reads Conversations between the project's team and its agents, holds the messages between the team and the project's agents, with the suggested questions. Insights, called Statistics before 13.2.49.71, shows how the project is going over its whole history: relevant changes, files touched, active days and contributors, what is blocked, the decisions waiting for someone, how Planning advances and your conversations that need a reply; Connections holds the hosting and the databases; Settings holds the project settings; Managers, where managers are invited and their access revoked, is there only for the project owner. Conversations appears only when the project has at least one other manager besides you: while you are its only person, which is what Managers says with Only you have access, the tab is not there, and a pending invitation does not count, because it is not a manager yet. The tab, and the conversations already written, come back by themselves as soon as a manager accepts, and leave again if the last other manager is removed; nothing is deleted.
The ... button at the right of the project name has Project settings, Copy project information and, when the open page has unread updates, Mark all as read. Copy project information copies a plain-text summary of the project: address, hosting, connectivity, databases, how many rules Staging and Production have and the planning counts, never passwords. Project settings shows the project address and your role, the project's Notifications choice (shared by everyone who manages the project), and the section to delete the project or, for a manager, to leave it. For the Overview, see What does the Overview of a project tell me?.