Due to the way make_code_span only starts buffering after the first line, its behavior can be different on subsequent lines. Escaped punctuation doesn't cover the backslash in any item span, so it gets lost.

$ cargo run -- -e
`\!\"\#\$\%\&
\!\"\#\$\%\&`
0..28: Start(Paragraph)
0..27: Code(Boxed("\\!\\\"\\#\\$\\%\\& !\"#$%&"))
0..28: End(Paragraph)
EOF

Not sure if there are any other items emitted by the first pass whose spans don't cover all of the input.