HTML5 ad runtime troubleshooting

HTML5 ad is blank after upload? Static validation is not enough

A creative can have valid files and still render blank when its JavaScript executes in the ad environment. Deep Audit runs the creative in a local browser to expose runtime failures before upload.

The short version

The ZIP passes a markup or packaging check, but the platform preview or live placement shows a blank, partially rendered, or broken ad.

What Ad-Preflight checks

  • Runtime JavaScript errors with file and line information
  • Failed asset requests and insecure network calls
  • Blank-render detection at each creative size
  • Overflow, animation, redirect, popup, and visual behavior signals

What it cannot guarantee

  • !A local browser run cannot reproduce every platform sandbox or publisher wrapper
  • !External services may behave differently at serving time
  • !A passing runtime report is evidence of readiness, not a platform approval guarantee

Run it in the desktop app or CLI

Designers and AdOps can drop a campaign folder into the desktop app and follow the visual report. If you work in a terminal or CI pipeline, the same checks are available through the CLI.

  1. 1.Run the standard audit first to remove packaging and markup failures.
  2. 2.Activate Deep Audit and run the creative in a real local browser.
  3. 3.Open the report and fix the first runtime error before chasing downstream symptoms.
  4. 4.Re-run all sizes and attach the report to the handoff.

CLI equivalent

npx @ad-preflight/cli package ./my-ad --fix

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