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    "browser": "144.0.7559.96",
    "playwright": "1.57.0",
    "pillow": "12.3.0",
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    "platform": "Linux-6.18.44-x86_64-with-glibc2.41",
    "headless": true,
    "network": "none: data URL image and set_content on about:blank; requests blocked",
    "cpu_throttling": "none",
    "device_scale_factor": 1,
    "cache": "new browser context for every run; no HTTP cache involved",
    "viewport_not_real_device": true
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    "650ms timer illustrates late image availability, not an expected production improvement",
    "Data URL / set_content fixture: no real navigation, network discovery or compression measurement",
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