After I upgraded my Mac from Yosemite to El Capitan developer beta, the scheme option button in Xcode 6.4 is disappeared from the tool bar:
But Xcode 7 beta works fine
Is this an El Capitan bug? Is there any solution to fix this apart from rolling back to Yosemite? Thank
You don't need that button; the same options are available from the Product menu. So even though it's a bug, you can work around it for now, easily enough.