Before → After difference: 9 target closes; T3 group TERM ends Chrome (143) → 9 target closes, then 1 browser close; Chrome exits 0; live survivors 0 → 0; milestone-to-return 247.975 ms → 122.695 ms What else changed: - All 9 nonempty measured heights identical: 320/375/430 → 304; 520/640/728/860/1000/1144 → 160. Attachment UUIDs differ by design. - Operation duration and process IDs/ports/temp paths vary; per-side measured values below. - No additional product behavior change observed in this fixture. ROW H — paired timestamped runtime capture Client request id: lead-27224-r1-capture-1 Environment: fs-04 / Linux 6.1.102 x86_64; Chrome for Testing headless shell 156.0.8078.70 (SHA-256 a313da592261ff1e342c1e507d315f25b1809006c0508f77ce86151d464d4ccb); checkout-selected Node v26.13.0; strace 6.8; Effect/platform-node 4.0.5; HtmlRender service harness, T3CODE_SERVER_BROWSER_SANDBOX=0; AppArmor disabled (N), LSM capability,selinux. Driver: harness, not a dev server/MCP transport. Both sides import their checkout own HtmlRender service. Epoch strace timestamps are UTC; JSONL also records ISO UTC and monotonic nanoseconds. Raw strace is unedited and includes controller cleanup AFTER survivor observation for U. TRIGGER H ===== BEFORE dd148481531a0a090780a2ade20588566db099a2 ===== MEASURED SUMMARY { "row": "H", "side": "Before", "directory": "/tmp/lead-27224-r1/capture/20261029T233409.127499Z-H-Before", "sha": "dd148481531a0a090780a2ade20588566db099a2", "server_pid": 186366, "wrapper_pid": 186383, "browser_pid": 186383, "outcome": { "time": "2026-10-29T23:34:12.436Z", "mono_ns": "156290535928563", "pid": 186366, "event": "operation_success", "result": { "attachmentId": "00000000-0000-4000-8000-000000000001-f6d80a58-0e6f-4c09-a066-da66f140d290-html", "title": "Synthetic lifecycle", "height": 144, "heights": [ [ 320, 304 ], [ 375, 304 ], [ 430, 304 ], [ 520, 160 ], [ 640, 160 ], [ 728, 160 ], [ 860, 160 ], [ 1000, 160 ], [ 1144, 160 ] ] } }, "milestone_epoch": 1793316852.188025, "milestone_description": "last measurement Target.closeTarget response written to CDP output pipe", "return_epoch": 1793316852.436, "release_ms": 247.975, "operation_ms": 1992.0, "close_epoch": null, "close_count": 0, "target_close_count": 9, "leader_release_exit": "+++ exited with 143 +++", "leader_exit_epoch": 1793316852.381124, "leader_ms": 193.099, "wrapper_exit": "+++ exited with 143 +++", "server_signals": [ { "epoch": 1793316852.192249, "relative_ms": 4.224, "syscall": "kill(-186383, SIGTERM) = 0 <0.000073>" }, { "epoch": 1793316852.383037, "relative_ms": 195.012, "syscall": "kill(-186383, SIGTERM) = 0 <0.000027>" } ], "live_survivors": [], "zero_survivors_after_cleanup": true, "png_sha256": null } ----- metadata.json ----- { "side": "Before", "row": "H", "sha": "dd148481531a0a090780a2ade20588566db099a2", "start": "2026-10-29T23:34:09.130871+00:00", "command": [ "strace", "-f", "-ttt", "-T", "-yy", "-s", "220", "-e", "trace=kill,exit_group,clone,clone3,fork,vfork,execve,write", "-o", "/tmp/lead-27224-r1/capture/20261029T233409.127499Z-H-Before/strace.log", "node", "--experimental-import-meta-resolve", "/tmp/lead-27224-r1/capture/scripts/harness.mjs", "/home/ubuntu/wt/pr-27224-before", "H", "/tmp/lead-27224-r1/capture/20261029T233409.127499Z-H-Before", "/tmp/lead-27224-r1/capture/scripts/real.py" ], "cwd": "/home/ubuntu/wt/pr-27224-before/apps/server", "driver": "HtmlRender.preview / HtmlRender.publish service harness; no dev server or database", "sandbox": "explicit T3CODE_SERVER_BROWSER_SANDBOX=0", "strace_pid": 186363, "driver_done_seen": true, "return_observed": "2026-10-29T23:34:12.438535+00:00", "browser_roots": [ 186383 ], "tracked_browser_pids": [ 186383, 186384, 186385, 186386, 186387, 186388, 186389, 186390, 186391, 186392, 186393, 186394, 186395, 186396, 186397, 186398, 186399, 186400, 186401, 186402, 186403, 186404, 186405, 186406, 186407, 186408, 186409, 186410, 186411, 186412, 186413, 186414, 186415, 186416, 186417, 186418, 186419, 186420, 186421, 186422, 186423, 186424, 186425, 186426, 186427, 186428, 186429, 186430, 186431, 186432, 186433, 186434, 186435, 186436, 186437, 186438, 186439, 186440, 186441, 186442, 186443, 186444, 186445, 186446, 186447, 186448, 186449, 186450, 186451, 186452, 186453, 186454, 186455, 186456, 186457, 186458, 186459, 186460, 186461, 186462, 186463, 186464, 186465, 186466, 186467, 186468, 186469, 186470, 186471, 186472, 186473, 186474, 186475, 186481, 186482, 186483, 186484, 186485, 186486, 186487, 186488, 186489, 186490, 186491, 186492, 186493, 186494, 186495, 186496, 186497, 186498, 186499, 186500, 186501, 186502, 186503, 186504, 186505, 186506, 186507, 186508, 186509, 186510, 186511, 186515, 186516, 186517, 186520, 186524, 186526, 186527, 186528, 186529, 186530, 186531, 186532, 186533, 186534, 186535, 186536, 186537, 186538, 186539, 186540, 186541, 186542, 186543, 186544, 186545, 186559, 186560, 186561, 186562, 186563, 186564, 186565, 186566, 186567, 186568, 186569, 186570, 186571, 186572, 186573, 186574, 186575, 186576, 186577, 186578, 186579, 186580, 186581, 186582 ], "live_survivors_before_controller_cleanup": [], "snapshot_time": "2026-10-29T23:34:15.471361+00:00", "strace_exit_code": 0, "cleanup": [], "adopted_reaps": [ { "time": "2026-10-29T23:34:12.206930+00:00", "pid": 186408, "wait_status": 15 }, { "time": "2026-10-29T23:34:12.206977+00:00", "pid": 186412, "wait_status": 15 }, { "time": "2026-10-29T23:34:12.207015+00:00", "pid": 186559, "wait_status": 15 }, { "time": "2026-10-29T23:34:12.391001+00:00", "pid": 186386, "wait_status": 15 }, { "time": "2026-10-29T23:34:12.391124+00:00", "pid": 186387, "wait_status": 15 } ], "end": "2026-10-29T23:34:15.497594+00:00" } ----- harness.jsonl ----- {"time":"2026-10-29T23:34:10.422Z","mono_ns":"156288522707281","pid":186366,"event":"driver_start","checkout":"/home/ubuntu/wt/pr-27224-before","row":"H","node":"v26.13.0","executable":"/tmp/lead-27224-r1/capture/scripts/real.py","noSandbox":"0"} {"time":"2026-10-29T23:34:10.444Z","mono_ns":"156288544301640","pid":186366,"event":"operation_start"} {"time":"2026-10-29T23:34:12.436Z","mono_ns":"156290535928563","pid":186366,"event":"operation_success","result":{"attachmentId":"00000000-0000-4000-8000-000000000001-f6d80a58-0e6f-4c09-a066-da66f140d290-html","title":"Synthetic lifecycle","height":144,"heights":[[320,304],[375,304],[430,304],[520,160],[640,160],[728,160],[860,160],[1000,160],[1144,160]]}} {"time":"2026-10-29T23:34:12.437Z","mono_ns":"156290537429998","pid":186366,"event":"driver_done","exitCode":0} ----- browser.jsonl ----- {"time": "2026-10-29T23:34:10.533470+00:00", "mono_ns": "156288632972113", "pid": 186383, "ppid": 186366, "event": "browser_start", "ps": " PID PPID PGID SID STAT ELAPSED CMD\n 186383 186366 186383 186383 Ss 00:00 /usr/bin/python3 /tmp/lead-27224-r1/capture/scripts/real.py --headless=new --remote-debugging-pipe --no-first-run --no-default-browser-check --disable-gpu --hide-scrollbars --mute-audio --block-new-web-contents --proxy-server=socks5://127.0.0.1:34599 --proxy-bypass-list=<-loopback> --force-webrtc-ip-handling-policy=disable_non_proxied_udp --no-sandbox --user-data-dir=/tmp/lead-27224-r1/capture/20261029T233409.127499Z-H-Before/t3-html-preview-rM0Ixv/profile about:blank\n"} ----- ps-after-3s.txt ----- Observed 2026-10-29T23:34:15.471068+00:00 (three seconds after driver_done / failed-driver observation) PID PPID PGID SID STAT ELAPSED CMD ----- ps-after-cleanup.txt ----- Observed 2026-10-29T23:34:15.471578+00:00 PID PPID PGID SID STAT ELAPSED CMD ----- stdout.log ----- {"time":"2026-10-29T23:34:10.422Z","mono_ns":"156288522707281","pid":186366,"event":"driver_start","checkout":"/home/ubuntu/wt/pr-27224-before","row":"H","node":"v26.13.0","executable":"/tmp/lead-27224-r1/capture/scripts/real.py","noSandbox":"0"} {"time":"2026-10-29T23:34:10.444Z","mono_ns":"156288544301640","pid":186366,"event":"operation_start"} {"time":"2026-10-29T23:34:12.436Z","mono_ns":"156290535928563","pid":186366,"event":"operation_success","result":{"attachmentId":"00000000-0000-4000-8000-000000000001-f6d80a58-0e6f-4c09-a066-da66f140d290-html","title":"Synthetic lifecycle","height":144,"heights":[[320,304],[375,304],[430,304],[520,160],[640,160],[728,160],[860,160],[1000,160],[1144,160]]}} {"time":"2026-10-29T23:34:12.437Z","mono_ns":"156290537429998","pid":186366,"event":"driver_done","exitCode":0} ----- stderr.log ----- ----- strace.log ----- 186366 1793316849.135433 execve("/home/ubuntu/.local/share/vite-plus/bin/node", ["node", "--experimental-import-meta-resolve", "/tmp/lead-27224-r1/capture/scripts/harness.mjs", "/home/ubuntu/wt/pr-27224-before", "H", "/tmp/lead-27224-r1/capture/20261029T233409.127499Z-H-Before", "/tmp/lead-27224-r1/capture/scripts/real.py"], 0x7ffcc27fb630 /* 58 vars */) = 0 <0.000338> 186366 1793316849.144916 clone3({flags=CLONE_VM|CLONE_FS|CLONE_FILES|CLONE_SIGHAND|CLONE_THREAD|CLONE_SYSVSEM|CLONE_SETTLS|CLONE_PARENT_SETTID|CLONE_CHILD_CLEARTID, child_tid=0x7f59b27ff990, parent_tid=0x7f59b27ff990, exit_signal=0, stack=0x7f59b25ff000, stack_size=0x1ffd00, tls=0x7f59b27ff6c0} => {parent_tid=[186367]}, 88) = 186367 <0.000071> 186366 1793316849.145264 clone3({flags=CLONE_VM|CLONE_FS|CLONE_FILES|CLONE_SIGHAND|CLONE_THREAD|CLONE_SYSVSEM|CLONE_SETTLS|CLONE_PARENT_SETTID|CLONE_CHILD_CLEARTID, child_tid=0x7f59b25fe990, parent_tid=0x7f59b25fe990, exit_signal=0, stack=0x7f59b23fe000, stack_size=0x1ffd00, tls=0x7f59b25fe6c0} => {parent_tid=[186368]}, 88) = 186368 <0.000050> 186366 1793316849.145574 clone3({flags=CLONE_VM|CLONE_FS|CLONE_FILES|CLONE_SIGHAND|CLONE_THREAD|CLONE_SYSVSEM|CLONE_SETTLS|CLONE_PARENT_SETTID|CLONE_CHILD_CLEARTID, child_tid=0x7f59b23fd990, parent_tid=0x7f59b23fd990, exit_signal=0, stack=0x7f59b21fd000, stack_size=0x1ffd00, tls=0x7f59b23fd6c0} => {parent_tid=[186369]}, 88) = 186369 <0.000074> 186366 1793316849.145931 clone3({flags=CLONE_VM|CLONE_FS|CLONE_FILES|CLONE_SIGHAND|CLONE_THREAD|CLONE_SYSVSEM|CLONE_SETTLS|CLONE_PARENT_SETTID|CLONE_CHILD_CLEARTID, child_tid=0x7f59b21fc990, parent_tid=0x7f59b21fc990, exit_signal=0, stack=0x7f59b1ffc000, stack_size=0x1ffd00, tls=0x7f59b21fc6c0} => {parent_tid=[186370]}, 88) = 186370 <0.000069> 186366 1793316849.148727 clone3({flags=CLONE_VM|CLONE_FS|CLONE_FILES|CLONE_SIGHAND|CLONE_THREAD|CLONE_SYSVSEM|CLONE_SETTLS|CLONE_PARENT_SETTID|CLONE_CHILD_CLEARTID, child_tid=0x7f59b1ffb990, parent_tid=0x7f59b1ffb990, exit_signal=0, stack=0x7f59b1dfb000, stack_size=0x1ffd00, tls=0x7f59b1ffb6c0} => {parent_tid=[186371]}, 88) = 186371 <0.000065> 186366 1793316849.152937 execve("/home/ubuntu/.local/share/vite-plus/js_runtime/node/26.13.0/bin/node", ["/home/ubuntu/.local/share/vite-plus/js_runtime/node/26.13.0/bin/node", "--experimental-import-meta-resolve", "/tmp/lead-27224-r1/capture/scripts/harness.mjs", "/home/ubuntu/wt/pr-27224-before", "H", "/tmp/lead-27224-r1/capture/20261029T233409.127499Z-H-Before", "/tmp/lead-27224-r1/capture/scripts/real.py"], 0x55cf60a8bd30 /* 58 vars */ 186371 1793316849.153170 +++ exited with 0 +++ 186370 1793316849.153195 +++ exited with 0 +++ 186367 1793316849.153210 +++ exited with 0 +++ 186369 1793316849.153235 +++ exited with 0 +++ 186368 1793316849.153249 +++ exited with 0 +++ 186366 1793316849.153927 <... execve resumed>) = 0 <0.000924> 186366 1793316849.172401 write(6, "*", 1) = 1 <0.000034> 186366 1793316849.173058 clone3({flags=CLONE_VM|CLONE_FS|CLONE_FILES|CLONE_SIGHAND|CLONE_THREAD|CLONE_SYSVSEM|CLONE_SETTLS|CLONE_PARENT_SETTID|CLONE_CHILD_CLEARTID, child_tid=0x7f508d7ff990, parent_tid=0x7f508d7ff990, exit_signal=0, stack=0x7f508cfff000, stack_size=0x7ffd00, tls=0x7f508d7ff6c0} => {parent_tid=[186372]}, 88) = 186372 <0.000062> 186366 1793316849.174171 clone3({flags=CLONE_VM|CLONE_FS|CLONE_FILES|CLONE_SIGHAND|CLONE_THREAD|CLONE_SYSVSEM|CLONE_SETTLS|CLONE_PARENT_SETTID|CLONE_CHILD_CLEARTID, child_tid=0x7f508cffe990, parent_tid=0x7f508cffe990, exit_signal=0, stack=0x7f508c7fe000, stack_size=0x7ffd00, tls=0x7f508cffe6c0} => {parent_tid=[186373]}, 88) = 186373 <0.000074> 186366 1793316849.174553 clone3({flags=CLONE_VM|CLONE_FS|CLONE_FILES|CLONE_SIGHAND|CLONE_THREAD|CLONE_SYSVSEM|CLONE_SETTLS|CLONE_PARENT_SETTID|CLONE_CHILD_CLEARTID, child_tid=0x7f5087fff990, parent_tid=0x7f5087fff990, exit_signal=0, stack=0x7f50877ff000, stack_size=0x7ffd00, tls=0x7f5087fff6c0} => {parent_tid=[186374]}, 88) = 186374 <0.000093> 186366 1793316849.174948 clone3({flags=CLONE_VM|CLONE_FS|CLONE_FILES|CLONE_SIGHAND|CLONE_THREAD|CLONE_SYSVSEM|CLONE_SETTLS|CLONE_PARENT_SETTID|CLONE_CHILD_CLEARTID, child_tid=0x7f50877fe990, parent_tid=0x7f50877fe990, exit_signal=0, stack=0x7f5086ffe000, stack_size=0x7ffd00, tls=0x7f50877fe6c0} => {parent_tid=[186375]}, 88) = 186375 <0.000090> 186366 1793316849.175345 clone3({flags=CLONE_VM|CLONE_FS|CLONE_FILES|CLONE_SIGHAND|CLONE_THREAD|CLONE_SYSVSEM|CLONE_SETTLS|CLONE_PARENT_SETTID|CLONE_CHILD_CLEARTID, child_tid=0x7f5086ffd990, parent_tid=0x7f5086ffd990, exit_signal=0, stack=0x7f50867fd000, stack_size=0x7ffd00, tls=0x7f5086ffd6c0} => {parent_tid=[186376]}, 88) = 186376 <0.000068> 186366 1793316849.204400 clone3({flags=CLONE_VM|CLONE_FS|CLONE_FILES|CLONE_SIGHAND|CLONE_THREAD|CLONE_SYSVSEM|CLONE_SETTLS|CLONE_PARENT_SETTID|CLONE_CHILD_CLEARTID, child_tid=0x7f508debe990, parent_tid=0x7f508debe990, exit_signal=0, stack=0x7f508deb6000, stack_size=0x7d00, tls=0x7f508debe6c0} => {parent_tid=[186377]}, 88) = 186377 <0.000061> 186366 1793316849.215967 write(19, "\1\0\0\0\0\0\0\0", 8) = 8 <0.000024> 186366 1793316849.236651 write(14, "\1\0\0\0\0\0\0\0", 8) = 8 <0.000057> 186376 1793316849.625368 write(14, "\1\0\0\0\0\0\0\0", 8) = 8 <0.000049> 186366 1793316850.281340 clone3({flags=CLONE_VM|CLONE_FS|CLONE_FILES|CLONE_SIGHAND|CLONE_THREAD|CLONE_SYSVSEM|CLONE_SETTLS|CLONE_PARENT_SETTID|CLONE_CHILD_CLEARTID, child_tid=0x7f504e7fb990, parent_tid=0x7f504e7fb990, exit_signal=0, stack=0x7f504dffb000, stack_size=0x7ffd00, tls=0x7f504e7fb6c0} => {parent_tid=[186378]}, 88) = 186378 <0.000093> 186378 1793316850.331159 +++ exited with 0 +++ 186366 1793316850.423468 write(20, "{\"time\":\"2026-10-29T23:34:10.422Z\",\"mono_ns\":\"156288522707281\",\"pid\":186366,\"event\":\"driver_start\",\"checkout\":\"/home/ubuntu/wt/pr-27224-before\",\"row\":\"H\",\"node\":\"v26.13.0\",\"executable\":\"/tmp/lead-27224-r1/capture/scripts"..., 247) = 247 <0.000092> 186366 1793316850.425623 write(1, "{\"time\":\"2026-10-29T23:34:10.422Z\",\"mono_ns\":\"156288522707281\",\"pid\":186366,\"event\":\"driver_start\",\"checkout\":\"/home/ubuntu/wt/pr-27224-before\",\"row\":\"H\",\"node\":\"v26.13.0\",\"executable\":\"/tmp/lead-27224-r1/capture/scripts"..., 247) = 247 <0.000053> 186366 1793316850.432676 clone3({flags=CLONE_VM|CLONE_FS|CLONE_FILES|CLONE_SIGHAND|CLONE_THREAD|CLONE_SYSVSEM|CLONE_SETTLS|CLONE_PARENT_SETTID|CLONE_CHILD_CLEARTID, child_tid=0x7f504dffa990, parent_tid=0x7f504dffa990, exit_signal=0, stack=0x7f504d7fa000, stack_size=0x7ffd00, tls=0x7f504dffa6c0} => {parent_tid=[186379]}, 88) = 186379 <0.000070> 186366 1793316850.432988 clone3({flags=CLONE_VM|CLONE_FS|CLONE_FILES|CLONE_SIGHAND|CLONE_THREAD|CLONE_SYSVSEM|CLONE_SETTLS|CLONE_PARENT_SETTID|CLONE_CHILD_CLEARTID, child_tid=0x7f504d7f9990, parent_tid=0x7f504d7f9990, exit_signal=0, stack=0x7f504cff9000, stack_size=0x7ffd00, tls=0x7f504d7f96c0} => {parent_tid=[186380]}, 88) = 186380 <0.000045> 186366 1793316850.433241 clone3({flags=CLONE_VM|CLONE_FS|CLONE_FILES|CLONE_SIGHAND|CLONE_THREAD|CLONE_SYSVSEM|CLONE_SETTLS|CLONE_PARENT_SETTID|CLONE_CHILD_CLEARTID, child_tid=0x7f504cff8990, parent_tid=0x7f504cff8990, exit_signal=0, stack=0x7f504c7f8000, stack_size=0x7ffd00, tls=0x7f504cff86c0} => {parent_tid=[186381]}, 88) = 186381 <0.000075> 186366 1793316850.433524 clone3({flags=CLONE_VM|CLONE_FS|CLONE_FILES|CLONE_SIGHAND|CLONE_THREAD|CLONE_SYSVSEM|CLONE_SETTLS|CLONE_PARENT_SETTID|CLONE_CHILD_CLEARTID, child_tid=0x7f4e37fff990, parent_tid=0x7f4e37fff990, exit_signal=0, stack=0x7f4e377ff000, stack_size=0x7ffd00, tls=0x7f4e37fff6c0} => {parent_tid=[186382]}, 88) = 186382 <0.000059> 186382 1793316850.434074 write(19, "\1\0\0\0\0\0\0\0", 8) = 8 <0.000039> 186380 1793316850.436421 write(19, "\1\0\0\0\0\0\0\0", 8) = 8 <0.000026> 186380 1793316850.436725 write(19, "\1\0\0\0\0\0\0\0", 8) = 8 <0.000033> 186380 1793316850.436950 write(19, "\1\0\0\0\0\0\0\0", 8) = 8 <0.000023> 186381 1793316850.437201 write(19, "\1\0\0\0\0\0\0\0", 8) = 8 <0.000022> 186382 1793316850.437410 write(19, "\1\0\0\0\0\0\0\0", 8) = 8 <0.000025> 186381 1793316850.437824 write(19, "\1\0\0\0\0\0\0\0", 8) = 8 <0.000031> 186382 1793316850.438537 write(19, "\1\0\0\0\0\0\0\0", 8) = 8 <0.000031> 186380 1793316850.442241 write(19, "\1\0\0\0\0\0\0\0", 8) = 8 <0.000037> 186379 1793316850.443152 write(19, "\1\0\0\0\0\0\0\0", 8) = 8 <0.000037> 186382 1793316850.443605 write(19, "\1\0\0\0\0\0\0\0", 8) = 8 <0.000028> 186366 1793316850.444916 write(21, "{\"time\":\"2026-10-29T23:34:10.444Z\",\"mono_ns\":\"156288544301640\",\"pid\":186366,\"event\":\"operation_start\"}\n", 103) = 103 <0.000030> 186366 1793316850.445091 write(1, "{\"time\":\"2026-10-29T23:34:10.444Z\",\"mono_ns\":\"156288544301640\",\"pid\":186366,\"event\":\"operation_start\"}\n", 103) = 103 <0.000043> 186381 1793316850.450360 write(21, "