I am building a Lightning Object Page for Opportunities.

Using the Tab Component (container) I have Detail and Related tabs which are working as expected.

However I try to add a 3rd tab for Chatter and save the page but the chatter tab is not saved?

Also tried to add News as a tab but again once I save the page it is not  there.

Added chatter and news to the right column works fine - but results in a lot of scrolling!

Would like to use tabs for some of these standard components to minimize user scrolling down the page.

Any Tips?