Photo Supreme's Formatted Vocabulary File (Data ▸ Export to Formatted
Vocabulary File) turns out to be Lightroom Classic's keyword list
format: plain text with Windows line ends, a top-level category in
square brackets, keywords a tab further in at each level. A test with
a file of that shape pins it down; a real export of 118 keywords read
and wrote back line for line. (Photo Supreme reads Lightroom keyword
files too: Data ▸ Import from Lightroom Keywords file.)
Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com>