_PLATFORM_PROFILE_URL had only patreon/subscribestar/hentaifoundry but
FC's extension_service.py recognizes 5 platforms. Any IR PostMetadata
with platform=deviantart or pixiv fell through _profile_url returning
None and the entry was silently skipped — explaining operator's
2026-05-25 finding that IR-migrated images had tags but no provenance
for the deviantart + pixiv subscriptions.
Pixiv caveat noted in comment: real profile URL takes numeric user_id
(https://www.pixiv.net/users/12345) but IR's PostMetadata.artist
stores display name. We slug the name and use it as if it were the id
so the artist->post->image linkage survives migration; the resulting
Source.url won't resolve in a browser and operator can fix via
Settings -> Subscriptions later if they want.
To recover existing IR-migrated state: re-run /api/migrate/tag_apply
on the existing manifest. Phase 4 is idempotent; new posts get
inserted only for the previously-skipped platforms.
Co-Authored-By: Claude Opus 4.7 (1M context) <noreply@anthropic.com>
bvandeusen