Hi,
There is no hotkey but I’ll add a zoom level indicator to next build, that should make it a lot easier to get back to 100%.
Or perhaps just a menu item that will reset the zoom level/font size. It doesn't need to have a hotkey. Doesn't matter to me, as long it's fairly easy to get back to the default level.
I second a menu item for resetting the zoom to 100%. That way a hotkey can be assigned via OSX's system preferences if needed.
/Carsten