Postmaster
An advanced postMessage devtools panel for Chrome
As of May 2026, Postmaster has 60 users in the Developer Tools category.
Usersup 71.4 percent+71.4%
60
60
Ratingno change0%
—
— reviews
Reviewsno change0%
—
Version
0.1.4
Manifest V3
History
2 snapshotsTracking since Apr 29, 2026.
View as table
| Date | Users | Rating | Reviews | Version |
|---|---|---|---|---|
| Apr 29, 2026 | 35 | — | — | 0.1.4 |
| May 26, 2026 | 53 | — | — | 0.1.4 |
| Now | 60 | — | — | 0.1.4 |
Permissions & access
- Permissions
- scripting
- Host access
- <all_urls>
Screenshots
About
Postmaster is a devtools panel for logging postMessages, which can be useful for debugging cross-window communication, including messages sent from iframes and MessageChannels. It includes a feature rich toolbar, making it a powerful debugging tool: FEATURES: LOGGING: Postmaster logs all messages with their origin, destination, time received, timestamp offset, and payload. Clear your logs at any time. FILTERING & SEARCHING: Add filters to prevent logging of unwanted or frequent messages, reducing noise. Once messages are logged, you can search through them using the search tool. Both filtering and search support targeting messages by origin, destination, or even the data payload — includes regex support for advanced use cases. SORT: Toggle how inbound messages are displayed, based on their time of receival. PRETTIFY: By default, Postmaster displays all message payloads as formatted JSON when applicable. For a more compact view, you can turn this off. PAUSE/PLAY: For debugging in scenarios with high volumes of exchanged messages, Postmaster supports a pause/play functionality to temporarily control the influx of logged messages.
Technical
- Version
- 0.1.4
- Manifest
- V3
- Size
- 103KiB
- Min Chrome
- 88
- Languages
- 1
- Featured
- No
Metadata
- ID
- nbbpoelfemohiaghnpmihgemalmcblka
- Developer ID
- u76a1c980294f40b58e6bb4873cba9562
- Developer Email
- [email protected]
- Created
- Dec 16, 2024
- Last Updated (Store)
- Dec 22, 2024
- Last Scraped
- May 26, 2026
- Website
- —
- Support URL
- https://github.com/arvinpoddar/postmaster
- Privacy Policy
- —
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Data sourced from the Chrome Web Store · last verified May 26, 2026.