PR https://git.cafe/pingdotgg/t3code/pulls/29308
head bc5ec0564ce4b91937ba78ab2d5c20fb3ea64793
main 71646e031a6dc9db1309b3b9dff597f872cf2fd3
Linux Electron 44.10.0, real desktop + owned backend, isolated state.
Project created through UI. Codex gpt-6.1-sol built and started HTTP app.
Real Codex follow-up on PR runtime returned HTTP 200 and title Download verification.
Playwright drove actual Electron browser guest buttons. No service mocks.
Main: two completed source artifacts retained full distinct bodies, but user Downloads had only one report.txt with mixed bytes.
expected {
  FIRST: '2fa42f492513a48387a6ff713ca9474be03860a6b2c774a31594c4ac4f342aec',
  SECOND: 'cbea69c7d8644502d26c9cb9d6fb38cd4f39c54a61d61ba0a00a8d405b30d20f',
  SINGLE: '1929620620806cbfca85612101401b3d95a8411d35a2122b9aa02322aee98a99',
  EXISTING: '729268c0c4f8c8041605e064664b8417dc2312213653b984435c8367ef7c72d9'
}
{"name":"report.txt","bytes":16777216,"sha256":"a9adbb05439f1124502ff717311c1a272aa1ebcde6c2235698cd47a0d849a2c9","completeBody":"CORRUPTED/MIXED"}
PR, empty Downloads: concurrent pair retained both complete original bodies:
expected {
  FIRST: '2fa42f492513a48387a6ff713ca9474be03860a6b2c774a31594c4ac4f342aec',
  SECOND: 'cbea69c7d8644502d26c9cb9d6fb38cd4f39c54a61d61ba0a00a8d405b30d20f',
  SINGLE: '1929620620806cbfca85612101401b3d95a8411d35a2122b9aa02322aee98a99',
  EXISTING: '729268c0c4f8c8041605e064664b8417dc2312213653b984435c8367ef7c72d9'
}
{"name":"report (1).txt","bytes":16777216,"sha256":"cbea69c7d8644502d26c9cb9d6fb38cd4f39c54a61d61ba0a00a8d405b30d20f","completeBody":"SECOND"}
{"name":"report.txt","bytes":16777216,"sha256":"2fa42f492513a48387a6ff713ca9474be03860a6b2c774a31594c4ac4f342aec","completeBody":"FIRST"}
PR, preexisting report.txt created through app download, then concurrent pair + single:
expected {
  FIRST: '2fa42f492513a48387a6ff713ca9474be03860a6b2c774a31594c4ac4f342aec',
  SECOND: 'cbea69c7d8644502d26c9cb9d6fb38cd4f39c54a61d61ba0a00a8d405b30d20f',
  SINGLE: '1929620620806cbfca85612101401b3d95a8411d35a2122b9aa02322aee98a99',
  EXISTING: '729268c0c4f8c8041605e064664b8417dc2312213653b984435c8367ef7c72d9'
}
{"name":"report (1).txt","bytes":16777216,"sha256":"cbea69c7d8644502d26c9cb9d6fb38cd4f39c54a61d61ba0a00a8d405b30d20f","completeBody":"SECOND"}
{"name":"report (2).txt","bytes":16777216,"sha256":"2fa42f492513a48387a6ff713ca9474be03860a6b2c774a31594c4ac4f342aec","completeBody":"FIRST"}
{"name":"report.txt","bytes":16777216,"sha256":"729268c0c4f8c8041605e064664b8417dc2312213653b984435c8367ef7c72d9","completeBody":"EXISTING"}
{"name":"single.txt","bytes":16777216,"sha256":"1929620620806cbfca85612101401b3d95a8411d35a2122b9aa02322aee98a99","completeBody":"SINGLE"}
Blacksmith: desktop build passed; vp test run apps/desktop/src/preview/Manager.test.ts: 61 passed.
No source edits, commits, pushes, merges, rebases, or label changes.
Not exercised: macOS, Windows, mobile, 100-name exhaustion, non-EEXIST copy errors, agent-initiated download exclusion. Web Chrome downloads bypass this desktop-only code.