Tabs can be switched by numeric keys or Shift + letter, generally corresponding to the first letter of the tab name:
Ctrl+click and Shift+click do different things depending on the context, usually described by the ? icon in the upper right corner.
Holding Shift changes tooltip to display cumulative production effects of all buildings, instead of a single building.
Window must be active for this hotkey to work, if you have other window (for example "picture in picture" video) active, it may not work.
Esc closes the dialog windows (like options, export, etc)