If you’ve got a page on one site (e.g. main site) and you want it to also appear on another (e.g. donate or intranet), click Groups in the top menu bar
click Nodes in the operations column of the site you want to add a page to
click the + Relate node button at the top of the nodes list
select the type of page you want to add on the Relate node list
Write the title (or keywords thereof) of the page you want to add, and select it from the dropdown list
click save
Your page now exists on both sites
[there are 2 ways of doing this - the one below gets the same result - do whichever is easier]
Select the page in the content list by ticking the box on the left
Select Add to a multisite from the Action dropdown list (top left of content list)
Then click Apply to selected items
Then on the on the 'Which multisite do you want….' page , select the site you want from the dropdown under Available multisites
and click the Add to multisite button.
Your page is now on both sites
Removing a page from a multisite
To remove a page from one site while keeping it on another,
select the page in the content list by ticking the box on the left
Select Remove from a multisite from the Action dropdown list (top left of content list).
Then click Apply to selected items
The next screen should ask you which site you want to remove your page from… but this function is currently broken. Please update this guidance when it’s fixed