Specter-dev Firefox

Specter-dev

Specter makes it easy to view and copy css properties without having to open the overwhelming browser console.
xHeader
Modify request and response headers. No ads, no malware.

Features & Capabilities

The inspector built for vibe coding. Point at what's wrong, say what you want, and hand it off — to your AI as a precise work order, or to another person as a comment that sticks to the exact element. No more screenshot → explain → retry loop.

Hover any element on any site to see its real CSS: tag, component, dimensions, font, color, background, padding, margin, border-radius. Press Ctrl+C (Cmd+C on Mac) to copy it in an AI-optimized format and paste straight into Claude, Cursor, or any assistant. One paste replaces a paragraph of explanation.

Annotate right on the page. Press P on any element and type the change you want — "reduce width to 320", "match the header font". Mark up as many elements as you need, then copy them all at once, each paired with your exact instruction. Your AI knows which element and what to do — no re-describing.

Share feedback with a person, not just your AI. Mark comments on a page, click Share, and Specter copies a link. Whoever opens it — on the same page, with Specter installed — sees your notes pinned to the exact same elements. Comments only: your CSS values and measurements never leave your screen. If the page changed and an element is gone, that comment is flagged instead of landing on the wrong spot. No account, no backend — the comments ride inside the link (or a small file for big reviews).

It's your browser inspector and Figma's measurement panel, rebuilt for the AI workflow — and tuned to spend as few tokens as possible while staying precise.

How it works:

  1. Click the Specter icon (or press Ctrl+Alt+Z — Ctrl+Option+Z on Mac) to activate on any page.
  2. Hover an element to see its style properties.
  3. Press C to toggle between Comment mode and Properties mode.
  4. In Properties mode, press the Alt key (Option on Mac) to toggle between the 5. Properties and Measurement viewer.
  5. Press P to mark it and type the change you want (optional).
  6. Press Ctrl+C (Cmd+C on Mac) to copy the elements — and your notes — for your AI. Or press L, then Share, to send them to a person.
  7. Paste into your AI assistant, or share the link with a teammate.
Note: If you want to send your specs directly to your AI agent, install the Vite plugin: https://www.npmjs.com/package/vite-plugin-specter

Features:

  1. Annotate on the page — press P to note a change on any element; mark several, copy as one instruction set
  2. Share comments with a person — mark notes, hit Share, send a link; they re-anchor on the same elements in the recipient's browser (comments only — never your CSS or measurements)
  3. CSS inspector — tag, component, dimensions, font, color, padding, margin, radius for any element on any site
  4. Figma-style measure — tap Alt (Option on Mac), then hover to see exact pixel gaps between elements
  5. Pin & measure — press M to pin one element, hover another to measure the distance
  6. Review panel — press L to see, edit, remove, or share everything you've marked Token-lean output — copies just what the AI needs, nothing it doesn't
  7. Works anywhere — production, staging, competitors; no setup

User Growth & Download Statistics

Manifest V2 Add-on
By:
Setu Kathawate
Daily users:
1
Version:
0.7.5 Last updated: 2026-09-06
Version code:
6466362
Creation date:
2026-06-28
Firefox add-on GUID:
specter@setugk.com
Firefox add-on numeric ID:
3031717
Weekly download count:
1
Firefox on Android:
No
Risk:
Moderate risk impact High risk likelihood
Permissions:
Content scripts matches:
  • <all_urls>
Size:
48.97KB
Email:
sp*****@setugk.com
Full description:
See detailed description
Source:
Firefox Add-ons Store
Data ingested on:
2026-09-09
Compare stats and ranking:

Contact the developer

Chrome-Stats does not own this Firefox add-on. Please use these information below to contact the Firefox add-on developer.
Developed by:
Setu Kathawate
Firefox Add-ons Store
https://addons.mozilla.org/firefox/addon/specter-inspector/
Email:
sp*****@setugk.com

Is Specter-dev Safe?

Risk impact
Risk impact measures the level of extra permissions an extension has access to. A low risk impact extension cannot do much harms, whereas a high risk impact extension can do a lot of damage like stealing your password, bypassing your security settings, and accessing your personal data. High risk impact extensions are not necessarily malicious. However, if they do turn malicious, they can be very harmful.

Specter-dev requires a few sensitive permissions. Exercise caution before installing.

Risk impact analysis details
  • Critical Allows access to all websites, posing a significant security risk as it can monitor and modify data from any visited site.
  • High ******* ******* **** *** ****** ***** *** ***** ** ******* **** ********* ********* ** * *********** *****
Risk likelihood
Risk likelihood measures the probability that a Firefox add-on may turn malicious. This is determined by the publisher and the Firefox add-on reputation on Firefox Add-ons Store, the amount of time the Firefox add-on has been around, and other signals about the Firefox add-on. Our algorithms are not perfect, and are subject to change as we discover new ways to detect malicious extensions. We recommend that you always exercise caution when installing a Firefox add-on.

Specter-dev is recently added, and hasn't been around long enough for us to gather enough data to accurately assess its risk level.

Risk likelihood analysis details
  • High This extension was recently updated in the past month. New updates may not be stable or safe.
  • High **** ********* *** *** **** ****** ********* ********** *** *** ** ****** ** *****
  • Medium **** ********* *** ***** ** *** **** * ******* *** ********** *** *** ** ****** ** *****
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