A Chrome extension that captures the content of postMessage.

Latest Version

Version
1.2.0
Update
August 22, 2021
Size
750KiB
Developer
Category
Users
1,000+
Rating
3 ★
Manifest Version
2
Web Store Status
Languages Support
English (United States)
See more
Permissions
Storage
See more

postMessage-catcher Extension

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.
Read more

Source Manifest.json

{"update_url": "https://clients2.google.com/service/update2/crx", "manifest_version": 2, "name": "postMessage-catcher", "version": "1.2.0", "description": "A Chrome extension that captures the content of postMessage.", "icons": { "16": "img/icon-16.png", "48": "img/icon-32.png", "32": "img/icon-48.png", "128": "img/icon-128.png" }, "author": "yang jin", "background": { "scripts": [ "js/background.js" ] }, "browser_action": { "default_icon": "img/icon-48.png", "default_title": "postMessage catcher", "default_popup": "popup.html" }, "content_scripts": [ { "matches": [ "" ], "js": [ "js/content-script.js" ], "run_at": "document_idle" } ], "web_accessible_resources": [ "js/injected-script.js" ], "homepage_url": "https://github.com/niexia/postMessage-catcher", "permissions": [ "storage" ]}
Read more

How to download and manually install postMessage-catcher extension for Chrome

Looking for a way to install postMessage-catcher extensions for Chrome, you can search for them in the Chrome Web Store, clicking the "Add to Chrome" button, and following the straightforward process.

However, you may need to install postMessage-catcher extensions manually, this article outlines two simple methods to effortlessly install postMessage-catcher extensions, whether they come as unpacked folders in compressed formats like .zip or as .crx files.

Method 1: Download postMessage-catcher extension and manually install through Drag &Drop

If you ever need to manually install a postMessage-catcher extension for Chrome, don't worry, it's a simple process. Just follow these easy steps, and you will have your extension ready to use in no time.

Step 1: Download the postMessage-catcher Extension by clicking the "Download CRX" button on the website.

Look for the postMessage-catcher extension you wish to install. Go to the website and download the postMessage-catcher extension package, which is usually a .CRX file and comes in a zipped file. Here ".crx" file is the format for postMessage-catcher extension that contains all the data.

Step 2: Extract &Arrange Files

Once the file is downloaded, extract that file into its own folder. Similarly, give that extension files a permanent home. In other words, keep it in a folder that you don't accidentally delete it because these files will be needed to make that extension work.

Step 3: Go to the Chrome Extensions Page

Open Google Chrome and in the address bar, type chrome://extensions; it will open the Google Chrome extensions page. Make sure that "My extensions" is selected in the sidebar.

Step 4: Drag and Drop the Extension

Now, go to the folder where you extracted the postMessage-catcher extension and drag &drop the extension file from there anywhere onto the extension page within Google Chrome.

Step 5: Complete the Installation

Once you drag and drop the extension file, follow the steps that Google Chrome takes you through. Similarly, if the extension file is of .crx file format, you will be required to review the permissions and then add the extension.

Now, you can manage that added extension as you would like to with any other Chrome extension that you added through Chrome Webstore. Its icon will also appear in the Google Chrome Menu on the right side of the address bar once you activate it.

Method 2: Download postMessage-catcher extension for Chrome and install in Developer Mode

This is another method to install postMessage-catcher extension manually, but the twist is that here, you install by enabling the developer mode option provided in Google Chrome. This mode is commonly used for testing extensions or running unpublished tools.

Step 1: Download the postMessage-catcher extension file

Select and download the postMessage-catcher extension by clicking the 'Download CRX' button on the website.

Step 2: Extract the downloaded contents

Convert the file to a ZIP file if it is in CRX format then extract the postMessage-catcher extension zip file or folder that you downloaded. Make sure you extract it using the same folder name and keep it safely in another folder, so you don't delete it by mistake. The extracted folder will be needed to keep your postMessage-catcher extension running.

Step 3: Open Chrome Extension Setting Page

In the address bar of Google Chrome, type chrome://extensions and open the Chrome Extension Page.

Step 4: Enable Developer Mode

After opening the Chrome Extension page, look at the top right side, and you will find the toggle option of "Developer mode."Simply enable that developer mode option.

Step 5: Load the Unpacked Extension

Once you enable the developer mode option, you will see the menu of Load Unpacked, Pack Extensions and Update. From that, select the option "Load unpacked."

Step 6: Select the Extension Folder

Once the pop-up opens upon clicking Load unpacked, select the postMessage-catcher extension directory and click on the "Select Folder "button.

Step 7: Confirm and Install

After you select an extension folder of a Google Chrome extension you're installing manually, confirm its installation for the final time and let the installation complete.

Conclusion

Here we've made a step-by-step guide on How to manually install postMessage-catcher extension in 2 ways. We hope this guide proves helpful.

Similar Extensions

icon

postMessage debugger Extension · Developer Tools 1,000+ 12 ★ 3.61KiB

icon

Shodan Extension · Productivity 1,000+ 136 ★ 27.6KiB

icon

post-message-logger Extension · Developer Tools 1,000+ 2 ★ 8.34KiB

icon

CSP Evaluator Extension · Developer Tools 1,000+ 29 ★ 297KiB

icon

tweak: mock and modify HTTP requests Extension · Developer Tools 1,000+ 190 ★ 3.22MiB

icon

DotGit Extension · Developer Tools 1,000+ 12 ★ 147KiB

icon

Trufflehog Extension · Developer Tools 1,000+ 8 ★ 34.61KiB

icon

postMessage Developer Tools Extension · Developer Tools 1,000+ 3 ★ 15.86KiB

icon

Hack-Tools Extension · Developer Tools 1,000+ 27 ★ 1.61MiB

icon

DOMLogger++ Extension · Developer Tools 1,000+ 4 ★ 652KiB

icon

postMessageObserver Extension · Developer Tools 1,000+ 0 ★ 23.07KiB

icon

Disable Content-Security-Policy Extension · Developer Tools 1,000+ 91 ★ 29.02KiB

icon

Requestly - Intercept, Modify & Mock HTTP Requests Extension · Developer Tools 1,000+ 1227 ★ 876KiB

icon

HackBar Extension · Developer Tools 1,000+ 52 ★ 1.56MiB

icon

retire.js Extension · Developer Tools 1,000+ 9 ★ 132KiB

icon

Burp Suite Navigation Recorder Extension · Developer Tools 1,000+ 3 ★ 279KiB

icon

OWASP Penetration Testing Kit Extension · Developer Tools 1,000+ 43 ★ 7.14MiB

icon

Untrusted Types for DevTools Extension · Developer Tools 1,000+ 3 ★ 39.16KiB

icon

FindSomething Extension · Developer Tools 1,000+ 34 ★ 512KiB

icon

YesWeHack VDP Finder Extension · Productivity 1,000+ 2 ★ 88.31KiB

icon

CORS Unblock Extension · Developer Tools 1,000+ 162 ★ 203KiB

icon

Modify Header Value (HTTP Headers) Extension · Developer Tools 1,000+ 46 ★ 94.33KiB

icon

Tamper Dev Extension · Developer Tools 1,000+ 29 ★ 532KiB

icon

Bishop Vulnerability Scanner Extension · Developer Tools 1,000+ 12 ★ 198KiB

User reviews

icon

Matt P (ID: 000000acd7fead05) Voted 1 ★ - Updated 01/20/2023 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 window...so you don't even see postMessages sent by the top window to child iframes. This makes this extension pretty useless as you can add a single "message" listener that logs messages in the devtools console to accomplish the same thing.