On Androis, Firefox Daylight gives a popup message when closing a tab in the list of tabs. If the list of tabs is longer than the screen, it blocks the bottom most tab's close icon. Therfore closing two (or more) tabs in rapid succession is not possible. This is something I often do, when I noticed I left open a lot of tabs that I don't need anymore I always have to wait for the popup disappears to close the bottom most tab. The popup could be smaller or block the tab from moving behind it.