When you switch a subtitle track you'll get `TypeError: Cannot read properties of undefined (reading 'ui')` in `captions.js`'s `captions.setup`, Because `captions.setup` is being called without proper `this` binding.
When you switch a subtitle track you'll get `TypeError: Cannot read properties of undefined (reading 'ui')` in `captions.js`'s `captions.setup`, Because `captions.setup` is being called without proper `this` binding.