The balloon comparison is strange. I would've just said that adding shift to a shortcut often reverses it... / for search and ? for search backwards, alt-tab to

The balloon comparison is strange. I would've just said that adding shift to a shortcut often reverses it... / for search and ? for search backwards, alt-tab to switch windows, alt-shift-tab to go the other way, ctrl-tab to go to next tab in Firefox, ctrl-shift-tab for backwards. It's incredibly common.