A browser extension for Chrome and Firefox that gives you an instant vibe of who's commenting. It displays coloured split-pill badges next to Reddit usernames showing their most active subreddits — visible at a glance without leaving the page.

Works on both www.reddit.com and old.reddit.com.

When an author link scrolls into view the extension queries the Arctic Shift API to retrieve that user's top subreddits by activity. A huge thank-you to Arthur Heitmann and the Arctic Shift project for making this data openly accessible — this extension would not be possible without it.

Note on activity counts: the count shown on each pill represents combined posts and comments the user has made in that subreddit during the configured time period, not posts-only.

• Split-pill badges — each badge shows [subreddit | count] with distinct background colours for the subreddit name and the activity count.
• All subreddits — not limited to any specific community; shows whichever subreddits a user is most active in.
• Sorted by activity — pills are ordered highest-count first.
• Click to search — clicking a pill opens an author-scoped subreddit search (/r/SUBREDDIT/search?q=author:USER) in a new tab.
• Visibility detection — only processes links currently in the viewport; new content loaded by infinite scroll is picked up automatically.
• De-duplication — already-labelled links are skipped; concurrent requests for the same username are coalesced into one.
• Rate-limit handling — respects x-ratelimit-* headers; shows a clickable retry badge when paused.
• 1-week cache (configurable) — user data is cached in chrome.storage.local and only re-fetched after expiry.
• Options page — configure API parameters, pill colours, cache duration, and pause/resume the extension without reloading the page.

Open the extension's options page (via the browser toolbar or chrome://extensions → Details → Extension options) to customise:

A live preview pill updates as you change colours. Click Save to persist, or Reset to defaults to restore all values.

1. Rename manifest_chrome.json → manifest.json
   (or copy it as manifest.json)
2. Open chrome://extensions/
3. Enable Developer mode (top-right toggle)
4. Click Load unpacked and select this folder

1. Rename manifest_firefox.json → manifest.json
   (or copy it as manifest.json)
2. Open about:debugging#/runtime/this-firefox
3. Click Load Temporary Add-on… and select the manifest.json file
   (for a permanent install, package as .zip and submit to AMO)

Tip: Keep both manifest files in the folder and swap which one is named manifest.json depending on your browser.

config.js              Shared namespace (RUV) and default settings
storage.js             chrome.storage.local wrappers, cache helpers
api.js                 Arctic Shift API fetch + rate-limit handling
ui.js                  Style injection, split-pill creation, DOM helpers
content.js             Main orchestration: scan, observe, processLink
options.html           Options page markup
options.js             Options page logic
manifest_chrome.json   Manifest V3 for Chrome/Edge/Brave
manifest_firefox.json  Manifest V2 for Firefox

The extension only sends Reddit usernames to the Arctic Shift API (arctic-shift.photon-reddit.com). No personal data is collected or transmitted elsewhere. All cached data is stored locally in your browser via chrome.storage.local.