In the release notes for Lightning, it states that Javascript buttons and links are not supported in Lightning, but Visualforce and URL buttons are. I have created the following Visualforce button on the Account object:
However, I am not sure how to access this button from the Account record detail page because it does not show up as one of the actions:
My question is, how are custom buttons shown on the Lightning Record detail page, and how do I add/remove custom buttons from the page?