Look closely at any web page.
CG Scope tells you how the page in front of you is put together. Measure distances, read an element's real spacing, type and colour, sample any pixel on screen, see what the page weighs, and save the images off it. It makes no network requests at all.
Most extensions that can read the page you are on could send what they read somewhere. This one cannot, and that is enforced by a build guard rather than promised in a paragraph.
The guard refuses to build if fetch,
XMLHttpRequest, sendBeacon, a WebSocket, a
remote script tag or a dynamic URL import appears anywhere in the
extension's source. Its own test suite breaks it on purpose and checks
that it goes red, because a guard that has never failed is decoration.
What it does
Five tools, one click away
Click the toolbar icon, pick a tool, and it appears on top of the page you are already looking at. Escape closes it. Nothing is installed into the page and nothing is left behind.
Ruler
Drag a box anywhere and read its width, height, position and ratio. Click any value to copy it, or copy ready-made CSS.
Inspector
Point at an element for its computed spacing, typography, borders and colours. Also lists every colour and font family on the page.
Color picker
Sample any pixel on screen, not only inside the page. HEX, RGB and HSL, each one click to copy, with your last dozen kept.
Images
Every image on the page in a grid, filtered by format, with dimensions and missing alt text flagged. Copy the URLs, copy a table, or save the files.
Page report
What the page weighs, broken down by resource type, and which images are loaded far larger than they are displayed.
Click a value to copy it.
Saved into a folder named after the site.
The interface, drawn with the extension's own stylesheet.
Verify it
Do not take the privacy claim on trust
Every extension says it respects your privacy. Here is how to establish it for this one in about two minutes, without taking anybody's word.
Watch it on the network tab
Open DevTools, go to Network, and use every tool on any page. Nothing appears, because nothing is sent. There is no server to talk to and no account to belong to.
Read the permissions it asks for
Four, listed below, each tied to a feature you can point at. There is no host permission and no access to your tabs or browsing history, which is what produces the alarming install warning on extensions that do read those.
Run the guard yourself
The source is public and the check that enforces all of this is one command. It scans the shipped code, refuses on any networking construct, parses every file, and its own test suite proves each guard is capable of failing.
.\build.ps1 check .\build.ps1 selftest
Permissions
What it asks for, and why
Every permission names the feature that needs it. A permission whose feature does not exist gets removed, and that has actually happened twice in this extension's history.
| Permission | What needs it |
|---|---|
activeTab |
Every tool. It grants access to the tab you are looking at, at the moment you click the toolbar icon, and then it expires. It is not standing access to anything. |
scripting |
How a tool is placed onto the page you clicked from. activeTab grants the right; this is the API that exercises it. |
storage |
The colour picker's last dozen colours and its copy-on-sample setting. Stored on your machine, never sent anywhere. |
downloads |
The Download button in the Images tool. Your browser retrieves the file you pointed at, the way it would if you clicked a link. |
Deliberately not requested: no host permissions and no
<all_urls>, no tabs, no
history, no cookies, no
webRequest, no webNavigation. Nothing observes
anything when you have not clicked the icon.
Privacy
The whole policy
This is the entire statement. There is no longer version.
CG Scope collects no data. It has no server, no account and no analytics. It makes no network requests of any kind. Nothing you do with it is transmitted, logged, shared or sold, because there is no mechanism in the extension by which that could happen.
Two things are stored on your own computer and nowhere else: the last twelve colours you sampled, and whether you have turned on copy-on-sample. Both live in your browser's local extension storage. Removing the extension removes them.
When you press Download, your browser retrieves the images you selected and saves them, exactly as it would if you had clicked a link. The extension does not see the file contents, and nothing about that request reaches us.
Questions: [email protected]