[earakely-scale]

What and why

This PR fixes two bugs in the browser's control connection from M5.10 (#459). I found them while building M8.5, the front door for a browser running alone.

The front door itself is no longer in this PR. A browser running alone will be a computer instead: a browser-24.04 base with a page driver, deployed like any other computer. That plan is M8.53, and there's a design note and an evaluation. 38cb86db removes the front door, so only the fixes are left.

• A popup never navigated. The connection attaches to each page as it opens. Chrome held each such page (waitingForDebugger) until it was told to run, even though the connection asked for waitForDebuggerOnStart: false. Start tabs were attached after they had loaded, so this never showed for them. A page opened by window.open stayed blank, though. Now each page the connection attaches to is sent Runtime.runIfWaitingForDebugger.
• The record's tab titles were stale. Headless Chrome sends no targetInfoChanged when a page's title changes. So the record kept the title Chrome gave a tab when it opened, which is its URL. Now the record reads each tab's URL and title (Target.getTargets) whenever it's read. A page's load refreshes its own tab too, so a tab that closes later keeps the title it had.

The protocol README describes both fixes.

How it was tested

• ruff check: clean.
• Protocol tests: 991 passed. Two of them are new:
  • each page the connection attaches to is told to run;
  • the record reads titles when it's read and when a page loads, and a closed tab keeps its last title.
• Integration, slow tier, on agent-environments-admin VMs (amd64 c6i.2xlarge, arm64 c7g.2xlarge): chromium_app_test, website_browser_test and computer_app_test: 12 of 12 passed on each arch, at b54fce11. The new test_a_popup_a_page_opens_loads_with_its_control_attached serves a page on loopback that opens a popup when Enter is pressed. It presses Enter through the computer's tools, then checks the record (both tabs, each at its URL with its title) and the window title. On amd64, with the runIfWaitingForDebugger call removed, the test fails: the popup's window stays "Untitled", and the record never shows its title.
• Earlier on this branch: the front-door runs on the VMs found both bugs. Greptile's first round (4/5) found two problems, both in front-door code that's now removed. It gave 5/5 once they were fixed.
• CI and Greptile on b54fce11: CI is 24/24, CodeBuild included. Greptile gave 5/5 with no findings.

🤖 Generated with Claude Code

Confidence Score: 5/5

The PR appears safe to merge; the latest test changes preserve the checks that the opened page loads.

Summary

The browser control connection now resumes newly attached pages and refreshes tab URLs and titles.

• Newly attached pages resume so popups can finish loading.
• Browser records keep tab titles and URLs current.

_{Reviews (5) · Last reviewed commit: "test(computer): the popup test's page op..." · Reviewed by Greptile}