SOURCE
summary
Distills how the source element actually behaves: video/audio use asynchronous selection that tries sources in DOM order and requires load() to switch, while picture makes the IMG the active renderer and selects synchronously from markup; explains why the media attribute was removed for video but kept for art direction in picture; shows the srcset parser state machine (URLs can contain commas), traces common double downloads to preload scanners and microtask timing, documents an Android 2.3 parser bug breaking picture polyfills, and outlines future plans like lazy loading and new image formats.
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chapters (13)
- 0:00Start
- 0:32Source Element
- 0:50History Lesson
- 6:50Synchronous Resource Selection
- 8:30Processing Model
- 11:57Responsiveness
- 14:28Media Attributes
- 19:41Sizes Attributes
- 27:19Css Syntax
- 30:09Double Downloads
- 32:11Meta Viewport
- 35:47Constrain on both the Width and Height
- 37:58Decorative Lazy Loading
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