Liferay by default persist information of portlet mode for page in user session level. When same user navigates again the page, persisted mode is used and rendered. For example,
Page1 have portlet1, portlet2 and portlet3.
Page2 have portlet2, portlet3 and portlet4.
If user is on Page1 and opens portlet2 in help mode, this combination of page and portlet mode is persisted by Liferay in user session level. If user then navigates to Page2 and comes back to Page1 then he gets portlet2 in help mode by default because he opened its help mode.
Persistance of this is by default only taken care for Page and PortletMode. But not WindowState. If you like Liferay to persist portlet WindowState in case of maximised state, there is just a simple way.
To inditate Liferay to persist maximized WindowState of portlet, turn on a property in portal-ext.properties.
Bydefault its value is false.
Now liferay will persist WindowMode as well 🙂 !