Mention Autocomplete Chat Block for Solid

Everything. The six people are a typed list in this file, the matching is a pure function, and the reply is picked from the first person your message mentions, written in a short script. Nothing is sent and no model runs, as the line under the composer says. To wire it for real, replace the list with your members, send the text where post says so, and turn the @Name tokens into ids on your server.

When the caret sits just after an @ that starts a word, with only letters after it. An email address such as maya@example.com does nothing, because its @ is inside a word. The list is cut at five people, matches the start of a name, and ignores case and accents, so "mar" finds Marek and "Hänne" finds Hanne.

Arrow Down moves focus into the list, where the arrow keys move the highlight and Enter picks. In the field itself Enter or Tab takes the first match, Escape closes the list, and with the list closed Enter sends and Shift and Enter add a line. The caret lands just after the inserted mention, so you can keep typing.

Under any message from someone else that contains "@You" there is a small "Mentioned you" line with an at-sign glyph. It is a word, not a color, and the message text carries the mention in medium weight with an underline. Replace the check with your own user id in a real app.

The list is a labelled listbox ("Mention a person") and the one status line reads how many people match and which key chooses. The log is a focusable region announced as a log, every message starts with a hidden name and time, and the field's description lists the keys. Avatars are hidden from assistive technology because names are always in text.

The same single column: the docked list sits over the bottom of the log and spans the width of the composer, rows show the role word beside the name, and the times in the gutter are always visible instead of on hover. The window keeps its height and only the log scrolls.