If the shortcut isn't listed next to the menu option, I'm never going to learn it unless I need to use it constantly. The top level menu items show the shortcut

If the shortcut isn't listed next to the menu option, I'm never going to learn it unless I need to use it constantly. The top level menu items show the shortcuts but the context menu items don't! Inconsistent! The funny thing is that I just tried to find the "shortcuts" list for Firefox and is is nowhere to be found in their menu or in Preferences! Do I need to find it on some webpage?!?