If you are searching something on reddit with ClearURL extension turned on, you won't be able to redirect to a results page, only through opening one of suggested results in new tab. I found that while you get redirected to an new page, URL contains space between searched text instead of "+"

PeekCSS is a CSS/design/image/font inspector — hover or click any element to read its computed styles, pull a whole page's color palette and fonts in one pass, and check contrast without opening DevTools. Built it because CSS Peeper (Chrome-only, 500k+ users) was never coming to Firefox.

Feature-wise:
hover/click inspection with grouped computed CSS and one-click copy (free, no account);
a page-wide palette + image scan with AA/AAA contrast badges and a font-usage breakdown (free account);
export to CSS vars/SCSS/JSON/Tailwind, bulk asset ZIP download, and font-pairing suggestions (Pro).

What it actually touches, since I know this sub cares more about that than feature lists:

• Permissions: storage, activeTab, downloads, and <all_urls> host access for the inspector itself (needed to read computed styles on any page you're on). One optional host permission for fonts.google.com, requested at runtime only if you use the font-pairing feature — never at install.
• Network calls: none, by default. The only request the extension ever makes is an optional license check if you buy Pro, and even that's gated behind Firefox's data-collection consent prompt. Font pairing (Pro) fetches Google's public font catalog client-side — nothing about your page or your fonts is sent anywhere.
• Size: ~103 kB total, no analytics SDKs, no bundled trackers.

It's a solo project, first extension I've shipped, live on AMO and the Chrome Web Store for about a week now. Genuinely want the nitpicks — permission scoping, manifest choices, anything that reads as a red flag to people who look at this stuff closely. What would make you trust an unfamiliar extension like this, or not?

Wanna give it a try?

Website: https://peekcss.com

AMO listing: https://addons.mozilla.org/en-US/firefox/addon/peekcss/

Hey everyone,
I built a Firefox extension called Minimal New Tab.

I originally made it for myself because I wanted a simple place to keep the sites I use every day, organized by folders and projects. Most new tab extensions I tried had too many widgets, so I wanted something calmer and more focused.

You can:
- save and reorder favorite sites;
- organize them into folders;
- customize the background and overlay;
- use keyboard shortcuts to add sites, create folders, and open settings;
- sync lightweight settings between Chrome/Firefox installations;
- export and import your setup when moving to another browser.

I didn’t originally plan to publish it, but I thought it might be useful to other people who organize their work or projects in a similar way.

Firefox Add-ons
Minimal New Tab

Chrome Web Store:
Minimal New Tab

Try the Live Demo

I’d appreciate any feedback, especially on what could be improved without turning it into another overloaded dashboard.

I posted this in the lemmy migration sub reddit and it was suggested i crosspost here

Hello!

I made firefox extension which shows ip address and country of the ip address.

https://addons.mozilla.org/en-US/firefox/addon/ip-data/

Review welcome.

Thank you.

Need help with identifying some of these extensions I had on a previous Firefox version 108. I had them on an old laptop on my FF, got a new new laptop (old one had blue screen of death) and basically have to start all over again with FF 151. No extensions carried over when I logged in except my little account pic. I always screenshot a pic of FF whenever there was an update so I can get it back to what I liked after an update, found the pics on a thumb drive. I know some of the extensions pictured were for Facebook and I do not care about them nor do I want them now. I know I had a picture resizer where you just hovered the cursor and the pic became bigger to see. Have to set up my FF configurations and figure out why my userchrome is not working too but that is another issue. So any help with these extensions were and maybe any recommendations for current ones would be appreciated.

While less popular than uBlock Origin, I can't imagine I'm the only uMatrix user.

Anyone know if there is a source for minimum settings to make various popular sites work in uMatrix?

Just got a clean firefox install, and playing bruteforce to find what works for different sites is annoying. I know it took a while before I was happy on my last install.

There are a ton of dictionary extensions and a ton of translation extensions, but I couldn't find one that did both properly. So I built WordGlance.

Select any word or short phrase, click the 📖 icon, and you get the definition, an example sentence using it, synonyms, antonyms, and the translation, all in one tooltip.

What it does:

• Definition + example of it used in a sentence
• Synonyms and antonyms
• Translation to 40+ languages
• Auto-detect source language, or set it manually
• Dark mode
• Works on desktop and mobile Firefox
• Caches results so repeat lookups are instant

No telemetry, no account needed. Open source, and the dictionary/translation APIs it runs on are open source too.

Firefox Add-ons: https://addons.mozilla.org/firefox/addon/wordglance/

Source: https://github.com/ShrekBytes/wordglance-extension

If you try it out, I'd love to hear what you like, what you don't, and any ideas for improving it.

Hi ;>

ConsentScope started as a Chrome-only extension, but Firefox has always been part of the plan. Today I'm happy to say the first Firefox version is live on AMO - and it's not the last.

What it does:

It shows you what websites do before you consent. It scans cookies, scripts, and consent banners in real-time, then flags potential GDPR violations like cookies set before consent or missing "Reject all" buttons.
Firefox actually care about privacy, so this felt like the right audience to build for.

Key features:

- Real-time cookie and script detection

- Flags cookies set before user consent

- Detects missing "Reject all" options and pre-toggled toggles

- Export scan results (JSON/CSV/PDF in Pro)

- No account required for basic use

Links:

- Firefox Add-ons: https://addons.mozilla.org/firefox/addon/consentscope/

- Chrome version: https://chromewebstore.google.com/detail/consentscope/bckfbligemognhkpoojinnlemmiaifmj

- Website: https://consentscope.pro

Feedback, bug reports, and feature ideas are very welcome. Thanks!

I built a Firefox extension that transforms any website into a Y2K/MySpace aesthetic - deep blacks, hot pink, falling glitter, CD and all.

Features:

- 2 themes - Hot Pink, Purple Glitter

- Draggable CD decoration

- Falling stars matrix with adjustable size and density

- CRT scanlines effect

- Per-site toggle so you can disable it on sites that break.

Would love feedback from the community!

https://addons.mozilla.org/en-US/firefox/addon/myspaced/

About two months ago, I made a few posts asking how people actually manage bookmarks.

The responses were surprisingly similar.

The tools were different, but the frustrations kept sounding the same:

A few patterns kept emerging:

• bookmark folders becoming graveyards
• saving things for "later" and never seeing them again
• keeping dozens of tabs open
• Googling the same thing twice because it's faster than finding it
• building weird systems with docs and notes apps just to keep track of links

The more comments I read, the more it felt like the problem wasn't saving things.

It was finding them again.

Most of us don't struggle to collect useful stuff.

We struggle to remember it exists when we actually need it.

That realization completely changed how I thought about bookmark managers.

I wanted something where:

• saving and finding take one click (Alt + S to save, Alt + W to find)
• organization happens automatically in the background (auto-tags, websites and topics)
• finding something months later feels effortless
• useful saves can resurface when you need them most
• collections are there when you're working on a project, but never required

So over the last couple of months, I built this Firefox Addon/Extension:

https://addons.mozilla.org/en-US/firefox/addon/stashed-bookmark-manager/

Would love to hear your thoughts.

What's the one thing that still feels missing from bookmark managers today?

I got tired of copy-pasting screenshots into my AI assistant, so I built SnapStack.

How it works:

• Click the browser extension → it captures the current tab
• The shot lands on a tiny server running on your own machine (127.0.0.1)
• Any MCP-capable client (Claude Code and others) reads your stack on demand — just ask it to "look at my screenshots"

It's 100% local: nothing uploaded, no account, no telemetry.
Server's on npm, the extension is in the Chrome/Edge and Firefox stores, all MIT.

Demo + setup: https://github.com/bgaze/snapstack-extension#readme

Would love feedback from people building MCP workflows — especially which other "give your AI eyes" tools you'd want it to play nice with.

Hi everyone, I've built a firefox add-on that can add left or right padding to any website which helps centering the content of that website.

You can watch the video showcase here: https://www.youtube.com/watch?v=a1UJ_XaRB5E

The source code is fully available at: https://github.com/rinn7e/damn-center-extension

If you like the project, you can buy me a coffee at: https://github.com/sponsors/rinn7e

Please leave a 5 star rating as well if you find the addon useful, thank you!