CURRENT BETA: index_beta_2026-03-12-v12.html
CURRENT CANONICAL DOCS: canonical-docs-2026-03-12-v12

Build from the latest uploaded authoritative file only.
If the current source build or docs are missing, uncertain, or stale, stop and request re-upload before editing.

V12 notes:
- fit modes patched against usable viewport
- aspect <-> resolution sync added
- 4:3 Tube TV mode strengthened
- thumbnails use contain instead of crop
- export is intended to remain WYSIWYG panel capture
- tooltip dwell and touch long-press behavior tightened
- tiny build tag visible when controls are shown