Add Processing's reference to Atom IDE.
ctrl+5 or use the option
Look for selection in Processing's reference of the contextual menu to look for the selected text. By default the query will be trimmed and its parentheses will be removed in case they exist. If the query is ok, Processing's online reference will be opened in a new tab.
Depends on Browser Plus for browsing inside Atom instead of relying on an external browser.
Good catch. Let us know what about this package looks wrong to you, and we'll investigate right away.