This should be really simple to do, and I use Google Chrome so not 100% sure it’s the same on all browsers.
But on Google Chrome, Marketo opens Marketing Activities & Lead Database in a separate tab and then the community in a separate tab again. Now if I close my Marketing Activities & Lead Database tab, I actually have to log back in to get back into Marketo to get back to my Marketing Activities & Lead Database tab, I can't get there from my community tab.
A link that takes me from the community to my Marketing Activities & Lead Database would be really useful and productive.