16.8Interview Talking Point

"Browser automation has evolved through four eras. Selenium 1 used JavaScript injection, WebDriver added native browser APIs over HTTP, CDP brought bidirectional WebSocket communication but was Chrome-specific and unstable, and now WebDriver BiDi combines standardization with bidirectionality. As of 2026 BiDi is the present, not the future: WebdriverIO v9 defaults to it, Selenium 4 exposes it at the low level with high-level APIs coming in Selenium 5, and it covers roughly 70% of what CDP offers across Chrome and Firefox. Even Jason Huggins — who started Selenium in 2004 — built his new tool, Vibium, BiDi-native from day one. The trade-off is that BiDi's feature set is still catching up to CDP in some areas, but the standards trajectory is settled."