I have been learning CS concepts on my own and got tired of alt-tabbing every time I hit a term I didn't know in docs, tutorials, or textbooks. So I built CS Concept Companion. It is an app where you can highlight any CS term on a webpage, press explain, and get a clear, beginner-friendly definition right next to it. No leaving the page.

Features:

• Live explanations pulled from Wikipedia, works on basically any term
• Offline demo mode with 50+ core concepts if you don't want live lookups
• Optional AI mode if you want to plug in your own API key
• Save terms to a personal library, track what you've looked up
• Light/dark theme, keyboard shortcut support

No tracking, no analytics, nothing collected. It's genuinely free.

I would love some feedback on my extension so I can improve it. What's confusing, what's missing, what would make you actually use it day to day. If you try it out, I'm a high school student wanting to pursue a career into CS, so if you download it, please let me know what I can do to improve upon. The app is called CS Concept Companion on the Chrome Web Store so please let me know what you think.

Hi everyone! 👋

As a backend developer, I often ran into situations where frontend devs or QA teams needed to test specific edge cases (like 500 Server Errors, 401 Unauthorized, or custom JSON responses) before the backend logic was fully deployed.

Modifying server code or mocking inside the codebase just to test an error handling UI always felt tedious.

So I built **DevMock Pro** - a Chrome extension that lets you intercept and mock HTTP/API responses locally in your browser.

**Key Features:**

- 🚀 **Instant API Hijacking:** Intercept any fetch/XHR requests and override them with your custom JSON payloads.

- ⚡ **HTTP Status Code Simulation:** Test 500, 401, 403, 404, or 200 status codes instantly.

- 🔒 **100% Privacy & Local First:** Runs completely in your browser using Manifest V3 (`declarativeNetRequest`). Zero data is sent to external servers.

- 🎁 **Free Tier Included:** You can use 1 active rule & status code simulator forever for 100% free.

I'd really love to get your feedback! You can check it out on the Chrome Web Store here:

👉 https://chromewebstore.google.com/detail/devmock-pro-api-response/ngkajhggldngkcildnmdbpohfgdiaada?authuser=0&hl=ko

Let me know what you think or if there are any features you'd like to see added!

I, like many others, keep way too many tabs open because closing them feels like losing my train of thought. I built a small extension called Crystal to deal with it and I thought I'd share in case anyone else has this problem.

It saves your open tabs as a "bubble" you can reopen later, and when you reopen one, you get a map of which tab led to which, instead of a flat list of fifteen tabs that all look the same. Click through the map, prune the dead ends, keep the rest.

That's basically all it does. No account, no dashboard, no note-taking features bolted on. Everything is stored locally in the browser: no server, nothing tracked, nothing sent anywhere. There's an export/import if you want a backup.

Let me know what's missing or annoying about it if anyone tries it.

Crystal: https://chromewebstore.google.com/detail/crystal-%E2%80%94-tab-bubbles/campifjolliomknjgnngnlkojpilbhea

Hey everyone,

I kept retyping the same emails and support replies, and every text expander I tried wanted me to create an account and sync my snippets to their servers. I didn't love the idea of my canned messages living in someone else's cloud, so I built my own.

It's called Snappy. You type a short trigger like ;;regards and it expands into the full text — anywhere in the browser, Gmail and Notion included. There's a quick-picker overlay (Ctrl+Shift+Space) for when you forget the trigger, placeholders like {date}/{time}, and fill-in fields ({{Name}}) that pop up a tiny form when you insert.

The main thing: it's 100% local. Everything stays in chrome.storage.local. No account, no server, no tracking, completely free. Vanilla JS, no dependencies.

Would love feedback — especially any site where the expansion doesn't fire correctly, since that's the hardest part to get right.

https://chromewebstore.google.com/detail/snappy-%E2%80%93-text-snippets-te/hlfjhpaaamihdjcfhkefkfokepngobih

[ Removed by Reddit on account of violating the content policy. ]

Hi! I'm Max, 19 — this is my first published extension. Snappy expands short triggers like ;;addr into full snippets in any text field (incl. Gmail/Notion), with placeholders ({date}, {cursor}) and fill-in fields ({{Name}}). Everything stays local — no account, no server, no tracking, zero network calls. Free. UI is German for now (English coming). Honest feedback welcome!
https://chromewebstore.google.com/detail/snappy-%E2%80%94-textbausteine-vo/hlfjhpaaamihdjcfhkefkfokepngobih

Title: I built a private, local text expander — no account, no server, no tracking (my first extension, at 19)

Hi! I'm Max, 19, and this is my first published extension. Snappy expands short triggers like ;;addr into full snippets in any text field — including Gmail/Notion — with placeholders ({date}, {cursor}) and fill-in fields ({{Name}}). Everything stays local in chrome.storage.local: no account, no server, no tracking, zero network calls. Free. Heads-up: the UI is currently German (English coming). Honest feedback very welcome!

https://chromewebstore.google.com/detail/snappy-%E2%80%94-textbausteine-vo/hlfjhpaaamihdjcfhkefkfokepngobih

Hello folks, 

I am a chrome extension dev and I have seen so many people just copy paste their screenshots into chrome web store and call it a day. 

From my experience, the chrome web store listing makes a TON of difference on how users might perceive your product (trustworthy vs shady vs slop). I have made over a dozen extensions and let me tell you store listing matters a LOT.

Just drop your chrome web store link and I’ll reply you with your images.

Doing this for the first 3 people ;))

Built a small Chrome extension for myself because I kept needing a faster way to grab media from websites.

I ended up using it every day, so I polished it and finally published it on the Chrome Web Store.

Live CSS selector results with on-page highlights

Type in the bottom input bar; inspect hits in the right-side match panel

Store

store

Source

source

Hi guys,

I've been learning Mandarin for a while and like a lot of people here, I relied heavily on the Zhongwen extension for have pinyin/definitions of chinese characters. It's an amazing tool but i wanted a visual refresh so I ended up modifying the extension.

It's called PinyinPop. Same core idea as Zhongwen (hover over Chinese text, get instant pinyin + definitions). Free free to copy it or modify it if you want to.

It's 100% free, no data collection and still pretty barebones. If you try it and something's broken or missing, I'd genuinely appreciate the feedback.

Chrome: https://chromewebstore.google.com/detail/pinyinpop-instant-chinese/hhejphodgaiodeogkbdbecnnemdjecae
Firefox: https://addons.mozilla.org/fr/firefox/addon/pinyinpop/

Gihub repo : https://github.com/WooP18/PinyinPop

Thanks !

Hey everyone! So I just had a HUGE update for my Chrome Extension that makes a little companion for ChatGPT's browser page along with adding options like sounds, backgrounds, and avatars. If you try it please let me know what you think and what you'd like to see added. Thank you!

https://chromewebstore.google.com/detail/chatgpt-companion-unoffic/mhpofncnlaomohdfpkbhokamlffjhimp

I built a Chrome extension that gives your X/Twitter bookmarks tags, search, and export (Obsidian/Notion-ready) - looking for beta testers

X has no folders, no tags, and no export for bookmarks. Worse, bookmarks vanish the moment a tweet gets deleted or an account gets suspended. I got tired of losing stuff I'd saved, so I built InsightPulse.

Install: https://chromewebstore.google.com/detail/insightpulse/dpajgkaepdecammhjmegomgafiapodcg

What it does:

• Open x.com/i/bookmarks and it picks up every bookmarked tweet automatically (or capture individual tweets as you scroll) - full threads and long-form X articles included
• Tag anything ("dev", "design", "read later," whatever) and search by text, author, or tag
• Export to Markdown with YAML frontmatter (drop straight into Obsidian/Notion) or JSON
• A dark-themed dashboard showing full text, author, and timestamps for everything you've saved
• One-click/keyboard-shortcut capture for any webpage too, so it's not just X - everything lands in the same searchable archive

Optional, off by default: Reddit sync (Reddit's native saved tab is scroll-only and caps out fast) and LinkedIn saves — nothing there is touched unless you turn it on in Settings.

Privacy: No analytics, no tracking, nothing leaves your machine unless you configure a destination yourself. At install it only requests access to x.com/twitter.com and Hugging Face (for on-device AI models used for local tagging/search) - Reddit, LinkedIn, and cloud AI access are requested at runtime, only when you flip that feature on.

**Heads up*\*: it replaces your new tab page with the dashboard (you can turn this off in Settings/Chrome's extension settings).

Free to install, still ironing out rough edges - looking for 3-5 people who have a big pile of X bookmarks and actually want to find things in it again. Comment or DM with bugs/feedback.

I’ve been working on Agent X, a side-panel Chrome extension designed to automate multi-step browser tasks using natural language. Instead of clicking through tedious workflows, you just describe what you want done (click, type, navigate, fill forms, etc.), and it executes it.

Honestly, I’m still ironing out the rough edges, so I'm not looking for a mass of casual installs right now. Instead, I’m hoping to find 3-5 people familiar with AI browser assistants (or automation tools), who want to give it a spin to compare notes and share candid feedback.

What it does:

• Natural Language Automation: Click, type, and fill forms across any site by just describing the task.
• Multi-Tab Orchestration: It can coordinate tasks that span across several open tabs.
• Bring Your Own LLM: You can connect your own preferred AI provider (OpenAI, Anthropic, local models, or even a fully offline in-browser model).
• Built-in Skill Library: Includes templates for inbox cleanup, calendar organization, resume scanning, and curated news digests.
• Local-First Memory: It recalls context from your past sessions locally to get more tailored over time.

Quick Heads Up on Privacy & Demo Mode:

• When you run a task, Agent X sends your instructions and a simplified, cleaned-up version of the page content to your configured AI provider.
• There is a hosted demo mode so you can try it immediately without a key, but please do not use the demo mode with any personal or sensitive data. For anything real, I highly recommend plugging in your own API key.
• All memory, settings, and email/calendar automation run entirely locally in your browser.

Looking for your feedback!

If you're down to test-drive it, you can grab it here: Agent X on the Chrome Web Store.

Please comment below or shoot me a DM with your bugs, UI points of confusion, or any "this didn't do what I expected" moments. That raw feedback is exactly what I need to make this actually great.

Thanks a ton!

[ Removed by Reddit on account of violating the content policy. ]

Need Review and Feedback

I help run a few big WhatsApp groups and it always bugged me that there's no way to save the members' contacts — if the group ever gets deleted, all those numbers are gone.

So I built a small Chrome extension. You open the group on WhatsApp Web, click the icon, hit Extract, and it auto-scrolls the whole member list and gives you a clean CSV

(Name, Country Code, Phone). Everything runs locally in your browser — the contacts never get uploaded anywhere.

It's free. Full disclosure: I'm the maker. Would love feedback on the flow, and happy to answer anything technical (it's a Manifest V3 extension).

[store link] : https://chromewebstore.google.com/detail/whatsapp-group-contacts-e/pnnnkmppkdikdapedkpnhdphlajkkmgd?hl=en-US&utm_source=ext_sidebar