[Feature]: Allow opting out of explicit Take control in the collaborative browser #17057

Request

Add a persistent option to opt out of the explicit Take control / Release control interaction mode for the collaborative browser. When enabled, an authorized person should be able to click, scroll, type, paste, or use touch in an agent-opened browser tab without first pressing Take control. The first intended interaction should reach the page rather than merely dismiss a gate.

The request comes from someone using T3 Code with other people/devices: interacting with the visible browser should not require declaring control each time. Keep the existing explicit mode available.

Current behavior and scope

Source review at 04ad17425a80484bf323a7d5076bd477a9499119 (upstream main, 2026-10-08):

• Web/desktop streamed previews expose Take control and Release control. ServerBrowserSurface.tsx drops pointer and other input unless controller === "you".
• Mobile exposes the same buttons in PreviewStreamWebView.tsx.
• The shared stream client refuses ordinary input unless this viewer already owns control.
• Server-side SessionControl.human requires explicit ownership; changing owners invalidates queued agent actions.
• Human-opened tabs already auto-grant control to the first authorized viewer in ServerBrowser.ts when agentId === null and the tab is unclaimed. This is useful existing behavior, but it does not cover agent-opened tabs or provide a configurable opt-out.
• The browser settings schema has no preference for automatic versus explicit control handoff.

Running environment reported 0.0.46-nightly.20261008.2801. These findings are from source inspection, not a manual client reproduction.

Expected behavior

• A discoverable preference enables interaction without the Take control step, including on agent-opened tabs.
• Human input takes priority over conflicting agent actions through the existing control mechanism, with a predictable way to return control to the agent. Avoid leaving the agent permanently blocked after ordinary interaction.
• Preserve read-only permissions and prevent an automatic claim from silently stealing another human viewer's active control.
• Apply consistent behavior to web, desktop, and mobile, including remote/tunnel connections and reconnects.
• Keep the change small; cover the control transition and first-input delivery with focused tests, and document the user-facing option.

Related work checked

No matching issue or open PR for this opt-out was found in searches for Take control, browser control, automatic/implicit control, and opt-out.

• fix(server): agent browser tools stop bloating history, fall back sensibly, and respect ownership #16956 addresses agents reading human-opened tabs and browser profiles; it retains explicit human control and does not add this option.
• fix(server): server browser input follows the preview control permission #16765 fixes preview-operation authorization, not automatic handoff.
• fix(server): environment-hosted browser tabs behave like a normal browser #16963 fixes other server-browser behavior, not this interaction mode.

Prepared with GPT-6.1-Sol through the Codex harness in T3 Code.