Add the Properties and Values page The value syntax the other protocol pages point at: the four lexical shapes, the three flag states, strings and their escapes, enums, colors, and the left-to-right application order. The through-line is that nothing is coerced. caption=hello and layout="vbox" are both errors, in opposite directions, and that is the point -- a value's shape is part of what it means, so the wrong one is reported where the mistake is. Also records why a hex color must be quoted: # begins a comment, so fg=#1e1e2e discards the rest of the line and the parser runs out of statement looking for the value.