After running a test on Beta I discovered this: If you leave the game page without accepting the score or if your opponent modifies the score (requiring you to reaccept) then the game correctly displays as active.
However; if you go to the home page and refresh(f5) then the game reliably disappears from the active counter even if it still requires your scoring attention for whatever reason. This is highly likely to affect correspondence games, assuming that closing and reopening the page has the same effect as refreshing.
Before and after refreshing:
