Chrome DevTools has a handy inspector for Local Storage and Session Storage, but is there nothing to inspect chrome.storage.sync?
chrome://sync-internals/ doesn't seem to display the actual contents of the synchronized storage per extension.
Storage Area Explorer extension provides a UI for viewing, editing, clearing, importing and exporting of chrome.storage.local, chrome.storage.sync, localStorage and sessionStorage.
In the future this feature may be implemented natively: https://crbug.com/848752.
Warning for ManifestV3: since devtools for service worker doesn't show storage, you'll have to open any visible page of your extension like the popup or options, right-click the page, then click "inspect", then go to Storage Explorer. If your extension doesn't have any visible pages, you can open chrome-extension://ID/manifest.json where ID is the id of the extension as shown in chrome://extensions page. Another method is to right-click any script from your extension in devtools (when you inspect the content script or service worker), then click "Open in a new tab". You can add a bookmark for this tab to open it quickly next time.
Visit chrome://sync-internals/
Click Sync Node Browser tab and wait for it to load (may give a blank screen or in progress cursor)
Click expansion triangle in the sidebar for Extension settings
Click on individual settings in the sidebar to see their values and other metadata
A poor workaround is to call get and obtain all the stored values. Of course, this doesn't let you conveniently edit them:
chrome.storage.sync.get(null, function callback(items) { console.log(items) });
I am trying to test sample code for web extension for browsers.
But, it doesn't work. I checked the console for Google Chrome and also for Firefox. It doesn't print anything. The following is my code:
manifest.json:
{
"description": "Demonstrating webRequests",
"manifest_version": 2,
"name": "webRequest-demo",
"version": "1.0",
"permissions": [
"webRequest"
],
"background": {
"scripts": ["background.js"]
}
}
background.js:
function logURL(requestDetails) {
console.log("Loading: " + requestDetails.url);
}
chrome.webRequest.onBeforeRequest.addListener(
logURL,
{urls: ["<all_urls>"]}
);
console.log("Hell o extension background script executed");
Am I missing something?
Your code is correct as written, it works and outputs to console.
If you are not seeing it, then you are, probably, looking at the wrong console.
1. Firefox
Mozilla describes what extension output can be seen in which console in their Debugging article.
Browser Console
The Browser Console no longer shows output from WebExtensions background pages by default. You can have it show output from all WebExtensions by selecting to display "Show Content Messages", which is available from the popup that opens when you click on the gear-like symbol "⚙️" in the upper right of the window, just to the right of "Requests". Depending on what you are doing, the Browser Console may show output from a WebExtensions Experiment. You can access the Browser Console from Tools➜Web Developer➜Browser Console (keyboard shortcut Ctrl-Shift-J, or Cmd-Shift-J on Mac).
In older versions of Firefox, this was the console to use to see output from extensions. However, that is no longer the case.
Browser Toolbox
If you have it enabled, you could also use the Browser Toolbox console. You can access it from Tools➜Web Developer➜Browser Toolbox (keyboard shortcut Ctrl-Alt-Shift-I; On a Mac: Cmd-Alt-Shift-I). If it is not available you can enable it through options from the Web Console settings page.
The console in this toolbox will show output from both scripts running in the background context and from content scripts. However, complex data will not be available (e.g. no Objects).
Add-on Debugger
This is what you should be using to view console output from scripts running in the background context of your WebExtension. This includes background scripts, scripts running in popups, options pages, and any other page loaded from the extension as the main URL for a tab, or iframe. You can access the Add-on Debugger though about:debugging➞Inspect (use the "Inspect" button that's associated with the WebExtension you are debugging; there's a separate button for each extension). This will open a new tab with the debugger. You can then click on the Console tab within that browser tab. This console will display only content from the WebExtension which you are inspecting.
Web Console
You, probably, are looking at the Web Console (keyboard shortcut F12) which is associated with only a single tab. This is what you want when debugging a webpage, but not an add-on's background scripts. For a content script which is injected in that tab, the console.log() output will show up in this console. However, you will not see output from any other portion of your add-on (e.g. not content scripts in other tabs, not background scripts, etc.).
2. Google Chrome
Showing the correct console for your extension is a bit more complex in Chrome. Console output will show up in only one of multiple possible places, depending on from what context the console.log() was executed. Each of the following DevTools are independent of each other and are displayed in separate windows, or tabs. Displaying in the associated tab (bottom or side) is the default for the DevTools associated with web pages and content scripts, because those are specific to the tab. For the web page/content script DevTools, you have the option of having it displayed in its own separate window, or docked inside the tab (side or bottom).
Background Scripts
As explained here, you have to go through multiple selections on a drop-down menu, to get to the chrome://extensions page (or you can type that in by hand as the URL, or use a bookmark) then select both a checkbox ("Developer mode") and then click on the "background page" link. Then, you have to select the "Console" tab on the window that pops up.
It is much easier to show what you have to do:
Content Scripts
Output will be shown in the regular web console (in the web Developer Tools). You can open it by pressing F12 (or other shortcuts) in the webpage in which your content script was injected. Each web console will only show the output from the scripts injected in that tab.
Doing the above with show the console.* output from your extension, but will result in the console JavaScript command line, debugger, etc. being in the context of the page, not the content script.
If you want to use the console JavaScript command line in the context of the content scripts which are injected into a web page, you need to select your extension's content script context from the drop-down menu in the upper left of the Console window. This drop-down menu will normally start with the value "top". The drop down will have selections for each of the content script contexts (one per extension that has script(s) injected).
Popup (built-in)
Right-click on your browserAction button and select "Inspect Popup". Alternatively, right-click within the popup and select "Inspect". Either will open the DevTools for the popup page. The popup will be kept open under more conditions than it normally would, but will still be closed if you switch tabs, etc.
Options
Right-click within the main content of the Options popup (not the title bar) and select "Inspect". This will open the DevTools for the options page.
Devtools extension panel
Same as Options above: right-click inside + inspect.
In case your panel intercepts the right-click or in a bugged Chrome 97/98, open devtools-on-devtools, then use its picker button in the toolbar of the Elements panel (or press Ctrl-Shift-C on PC) to select your panel in the original devtools window.
Tab or popup (detached) with a page from your extension
When a tab or a detached popup window is focused, you can open the DevTools by pressing F12 (or other shortcuts), or by opening the context menu (right-click) and selecting "Inspect".
Note, the "detached popup" here means a window without an address bar, which is created using window.open or chrome.windows.create. There was another type called "panels", but it's no longer supported in modern Chrome.
Which console are you viewing in for the logs?
If you are viewing console on a tab, then that is the wrong place.
Open settings / Extensions or in a new tab type
chrome://extensions
Under your extension click on "background page" link which is where you can watch for logs
**Make sure Developer mode is checked
Yes for Chrome you have to click the background page link mentioned, but it won't be there unless you set it to be persistent:
"background": {
"persistent": true,
"scripts": ["background.js"]
}
My background page saves data about the current active tab to chrome.storage.local. For arguments sake lets say it's the page title. Multiple page titles will be in there if the user has multiple tabs open.
When the browser action button is clicked I want to open a new tab with my internal extension page showthedata.html (not an external URL) which will show the data saved for the active tab.
Ideally I'd want to open showthedata.html?tabID=123 which would then pull the corresponding data
I must be missing something basic, but how can showthedata.html show the data relating to the active tab?
If you use your extension's URI as the URL of your new tab, it will allow you to use the API's messaging and storage systems from your new tab.
Create a New Tab
chrome.tabs.create({url: "chrome-extension://<your_extension_id>/path/to/file.html"})
Once you get that set up, you can pass variables to or request variables from your new tab via the Chrome API messaging system or storage system (provided you've built the proper functionality into your extension's various parts).
Note: The chrome.tabs namespace is not accessible from within a Chrome tab. It must be called from either your background script(s) or popup.
simple question about the ability of chrome extensions.
Is it possible to for example hit an extension button and write the url (or other content of a page) to an endpoint of a open tab. For example, tab 1 is a web application that gathers bookmarks (so not locally stored) and if I hit a button in tab 3 I want to make a POST call to tab 1. Or can something like this be achieved by storing information in the Chrome storage which can then be read by the application in tab 1?
So quite simply:
tab 1 (:web application) - gets POST request -> tab 3 (:just a web page) through the click of a button of an active extension. I know if this would exist it could lead to some security issues, hence the question.
I have a chrome extension which allows the user to perform actions and build up data. How can I get my chrome extension to open a new tab to allow my user to interact with the data they've accumulated? I could build a separate web app service where I pass the users data to. I currently persist the users data in local storage but I want a way for them to view/edit that data.
Not sure what exactly to google to get a chrome extensions to launch a new page under it's url...
Edit:
Ideally I'd like for my user to press a button from the popup.html popup to open up the new tab, if possible.
I got it to work, basically from the popup.html page I can make this javascript call,
chrome.tabs.create({url: chrome.extension.getURL('dashboard.html')})
where 'dashboard.html' is file belonging to my chrome extension.