postMessage-catcher - Chrome Web Store
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A Chrome extension that captures the content of postMessage.

An effective development tool to help you capture all messages posted and received on the current page. It aims to provide an easier debugging experience when you need to communicate with other iframes. Contributions are welcome to the Github project.

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Matt PJan 20, 2023

Tried this in Jan 2023 to understand how the youtube javascript embed API interacts over postMessage. This extension doesn't catch or report any of the postMessages that may happen in sub-iframes (e.g. not in the top window). So if you prototype something in codepen or whatever you won't see the postMessages in this extension. It appears (limited testing) it only reports postMessages RECEIVED by the top you don't even see postMessages sent by the top window to child iframes. T... Show more

1 out of 2 found this helpful


  • Version
  • Updated
    August 22, 2021
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    English (United States)
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