If you look at the markdown on community/index.md, you will see some links are directed to open in place and some in a new tab/window:
For example:
<li><a href="https://services.greenbuttondata.org/ThirdParty" target="_blank">Green Button Data Sample/ThirdParty</a></li>
<li><a href="http://energyos.github.io/OpenESPI-GreenButton-API-Documentation/">Green Button Connect My Data Developer Guide</a></li>
Note that one has target="_blank" and the other does not. The one with "_blank" will open in a new tab or window based on browser settings, I think.
I believe this is the preferred behavior. In any event, the links on the page should be consistent.