The Anatomy of a Click
summary
Browser clicks go through low‑level OS hooks rather than just dispatchEvent: automation tools like Puppeteer and Selenium drive input.dispatchMouseEvent which Chrome maps into platform calls such as CGPostMouseEvent, producing roughly ~40 events fired for a single click (pointer, enter/leave, mouse down/up, activate, etc.). React normalizes events with a one root listener and synthetic event layer (mouseenter is synthesized from mouseover/out), so firing a native mouseenter or click may not trigger the framework the way tests expect, causing cross‑OS flakiness.
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chapters (26)
- 0:00Intro
- 0:47Framework Internals
- 1:24Events
- 1:40Automation
- 1:51JavaScript
- 2:25Why is this hard
- 2:37React
- 3:08Dom
- 6:24Click Handler
- 6:44Capture
- 7:29Bubble
- 8:11JQuery
- 8:43Event Plugins
- 10:05Why is this confusing
- 12:22Automation tools
- 12:35Chrome Debugging
- 12:48Chrome Dev Tools
- 13:20Mouse Events
- 13:33Chrome Driver
- 13:55Multi Monitor
- 14:10CG PostMouse
- 15:05Browsers
- 16:29Testing
- 17:47Recap
- 18:56Conclusion
- 19:52Outro
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