server.Server.typed_key_bindings

table narrows the listing to one key table. A table with no bindings lists empty, since tmux keeps no empty table to refuse.

Every table is fetched and the narrowing done here. tmux 3.7 through 3.7c send a listing of exactly one binding to the message log instead of printing it, so list-keys -T on a table holding one binding answers with nothing. Across every table, that happens only on a server with a single binding left, which lists none on those releases.

Errors

Returns Error::UnsupportedCapability below tmux 3.7, which has no list-keys -F; Self::key_bindings reads the bind-key lines those releases print. Returns Error::DecodeListing when a row does not decode, and an error when tmux cannot be reached or refuses the listing.