Expression Editor Keyboard Shortcuts *BUG*
I'm pretty sure this is a bug. When editing code, I often delete specific parts by selecting words (Shift+option+arrow keys). For some reason in the new expression editor, using option+arrow keys will jump words but adding in shift to select reverts it back to selecting letter by letter for some reason. It looks like this is now used to select multiple lines, but that's kind of an unexpected behavior. Usually, in code editing software, multi-line select is handled by option+drag.