Ctrl+H took the pending syllable as the query, but the keys typed after
it started a composition of their own: gk, Ctrl+H, s showed 하ㄴ, and r,
Ctrl+H, k showed ㄱㅏ. transstr now composes from a pending text, so
the search goes on where the syllable left off. Escape ended the search
and dropped the syllable it had taken; it puts it back as pending text.