Real web app checkout evidence
Linux; Node v26.12.1; git 2.43.0; Chromium 156.0.8078.4; 1280x800; light theme.
Fresh databases; synthetic GitHub hosting; real git and local bare remotes.
Base: 59e64eef881632a23f89c4138bcf37f23d92bf93
Head: 91c868e597e028b17da7bb4c8907ed1d509fcec7

before-t3code
Browser outcome: failed
Preserved user branch: t3code true
Visible error: Failed to materialize pull request #94 branch topic as t3code/pr-94/topic.
Final consecutive screenshots 500 ms apart: identical pixels

after-t3code
Browser outcome: passed
Preserved user branch: t3code true
Created branch: t3code-pr-94-topic
At fork PR head: true
Upstream: contributor/topic
Fork content: Fork PR content
Final consecutive screenshots 500 ms apart: identical pixels

before-prefix
Browser outcome: failed
Preserved user branch: t3code/pr-94 true
Visible error: Failed to materialize pull request #94 branch topic as t3code/pr-94/topic.
Final consecutive screenshots 500 ms apart: identical pixels

after-prefix
Browser outcome: passed
Preserved user branch: t3code/pr-94 true
Created branch: t3code-pr-94-topic
At fork PR head: true
Upstream: contributor/topic
Fork content: Fork PR content
Final consecutive screenshots 500 ms apart: identical pixels