- Rename _escHandler to _keyHandler (now handles nav keys too)
- Store counter reference (lb._counterEl) to avoid DOM query on every nav
- Remove dead 'let counter = null' and 'hasNav' closure variable
- Use lb._navImages directly in keyboard handler for consistency
- Add null guard on lb.querySelector('img') in _navigateLightbox
- Inline _updateLightboxCounter one-liner
- Fix CSS section comment 'Image lightbox close' → 'Image lightbox'
- Fix CHANGELOG placeholder (#PR → #2967)