Extensions are guests. Guests do not own navigation, default search, or the process lifetime of the tab. If you want an agent that builds and browses inside the browser, fork Chromium.
Xplor is that fork: Grok (and agent tooling) at source level — default search, per-page ask, toolbar, always-on local gateway.
Extension vs fork
| Capability | Extension | Fork |
|---|---|---|
| Default search / new tab | Fighting Chrome | Native |
| Always-on local gateway | Fragile background page | Process you own |
| CDP + higher-level API | Partial / brittle | First-class |
| "Grok it" on every page | Content script games | Built-in |
| Not affiliated with xAI | Say it anyway | Say it anyway |
The gateway is the actual product. CDP plus a higher-level API so any external agent can drive the browser — not a chat overlay bolted onto someone else's Chrome.
What I care about measuring
Can an agent open a page, extract structure, write code in a side panel, and keep session state without the extension getting killed? That is a harness question. Chromium internals matter because the agent control plane has to sit under the UI chrome, not on top of it.
Live: https://xplor.sh · source: https://github.com/daniel-farina/xplorer
Not affiliated with xAI. Power user of coding agents and browsers — shipping the fork.