libhangul, and so fcitx5-hangul, joins two lone consonants into the
compound jong they make (rt → ㄳ, split again by a vowel: rtk → ㄱ사),
and by default reorders a vowel typed before its consonant (kr → 가);
strans committed the first jamo and started over. Backspace on a lone
ㄳ leaves ㄱ, as on a syllable.
The three jamo index tables and their -1 macros were the cho, jung, and
jong arrays inverted by hand, bounded by a Jrange the callers had to
respect; a linear scan of the arrays says the same in ten lines.
Hojun-Cho
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