How --grep, --filter ~/!~, /, ?, and :tag patterns interpret
case. Smart matches less / ripgrep / vim smartcase: a pattern with
no uppercase characters is treated as case-insensitive; one with any
uppercase character is case-sensitive.
Controls auto-exit on end-of-file. Off (default) never quits.
Second (less -e) quits on the second forward-motion that lands at
EOF in a row. First (less -E) quits the moment a forward motion
lands at EOF.