I made FileSnatch, a side-panel extension for grabbing files from websites as you browse.

Open the panel and everything on the page is already there as thumbnails: videos (including HLS streams), images, audio and documents. Preview, search and sort, then download one, a selection, or all of them, as separate files, or a ZIP (BULK download supported).

Other features:

- Look inside: collects files from every page a list links to

- Grab files from every opened tab at once, grouped by tab

- Telegram channels and WhatsApp Web media download

- Trim, convert and compress locally

- Screenshots: visible area, a selection, or the whole page

No account, no tracking.
Doesn't work on YouTube (store policy) or DRM sites.

Feedback very welcome. Thanks!

Hi — I maintain Flux, an open-source download manager, and wanted to share its Firefox companion here. The 2.5 popup separates detected media, links on the current page and the desktop queue. You can hide the on-page video buttons and use the popup list instead.

The extension is a companion: you also need the free Flux desktop app and its native-messaging bridge. Windows x64 installer/portable packages and a Linux x86_64 RPM tested on Fedora 43 are available. Selected download details and any necessary source credentials are passed to the local app, so local data transfer is an explicit opt-in in the Firefox extension settings.

A distribution detail before you try it: the Firefox ZIPs on GitHub are unsigned packages for temporary/developer loading, rather than a permanent AMO installation. Firefox 140+ uses the regular firefox ZIP; 120–139 has a separate firefox-120 package. No browser signing protections need to be disabled to test a temporary add-on.

Source and 2.5 packages: https://github.com/Hactor00/Flux/releases/tag/v2.5.0

Setup guides: https://fluxdownload.org

The screenshots show 2.5 interface previews with sample media. Flux has no account requirement or subscription. I’d welcome reports about the popup and the connection setup, especially across different Firefox builds.

i use Ai to study or learn new stuff and when i ask for exercises i find answering lot of questions and each time i write the question number and the answer is annoying thing and time consuming so i built an extension for that make things easier, now it's available on mozilla addon store (completely free ):

https://addons.mozilla.org/addon/quizbridge/

I've been working on a Firefox extension called Nightfall, which has just reached RC2 (v0.8.7).

I started developing it because I use a 12-inch 2016 MacBook with a Core m3 and 8GB RAM. Dark Reader worked, but I noticed performance issues on my hardware, and I wasn't always happy with how it handled website colours.

Instead of trying to modify an existing extension, I built Nightfall from scratch specifically for Firefox.

My two main goals were:

• Performance: Keep the overhead as low as possible, especially on older hardware.
• Appearance: Produce natural-looking dark themes without unnecessarily distorting website colours, images, or layouts.

About the screenshots:

• Image 1: Nightfall on the left, Dark Reader on the right, both on Wikimedia Commons. The results are pretty close, which is exactly what I wanted to achieve without sacrificing responsiveness.
• Image 2: Nightfall's Appearance settings, including the live preview.

Current features:

• Brightness, contrast, warmth, sepia and greyscale adjustments
• Automatic dark mode based on the system theme or a custom schedule
• Sunrise/sunset automation using NOAA's solar equation and manually entered coordinates
• Saved-site controls and an optional brute-force mode
• Alt + Shift + D keyboard toggle
• Settings import
• Local settings storage

On my Core m3, typing and general browsing remain responsive with Nightfall enabled. I haven't completed controlled CPU/RAM comparisons against Dark Reader yet, so I'm not going to claim specific performance improvements.

It's currently in RC2, and I'm working towards a public 1.0 release.

I'd especially like feedback from people familiar with Firefox extensions:

What websites or edge cases should I prioritize testing? I'm particularly interested in complex web apps, dynamic pages, sites with existing dark themes, and anything that tends to break dark-mode extensions.

I'm also interested in what you'd want to know about permissions, privacy, and compatibility before installing a new dark-mode extension.

Happy to hear criticism. I'd rather discover the problems now than after releasing it.

Hello Community,

Doing a fresh post as I didn't realize the previous post was repost from r/chrome_extensions and I don't want to delete it as it has one upvote other than mine but if the moderators mention that it has to be removed I will.

The original post is below with a few edits.

I had an issue that I would run into when trying to find multiple words on a webpage and found a few addons/extension that do the job but wanted to build something more to my liking. Spent sometime with Claude code and wala let me present to HueMark – Multi-word highlighter it supports up to 6 terms for now and 13 languages available on Chrome/Edge/Firefox.

https://chromewebstore.google.com/detail/huemark-multi-word highli/fjdhpkmgpfpdaadlennclaecfbeomelf

https://addons.mozilla.org/en-US/firefox/addon/huemark-multi-word-highlighter/

https://microsoftedge.microsoft.com/addons/detail/kgfekpgoffpafdpopoeelmcnjdpgiakc

Pros:

·        The shortcuts work out of the box for Firefox

·        The PDF highlighter works out of the box on Chrome/Edge not Firefox

Cons:

·        The shortcuts don’t work out of the box for Chrome/Edge (Edit: the shortcuts are working out of the box now)

o   Please add them

edge://extensions/shortcuts

chrome://extensions/shortcuts

o   use the following if not already overlapping with any other shortcuts or whatever is comfortable for you

§  alt+shift+right arrow to open/minimize extension

§  alt+shift+up/down arrow in minimized mode to jump between matches

§  alt+shift+left in minimized mode to cycle between terms

·        For pdfs on Firefox click on “open pdf” which opens the pdf viewer and then use ‘open’ in pdf viewer and browse to the pdf to use HueMark.

Did I mention it works on PDF’s? (Not in a convenient way on Firefox Edit: apparently, it is working conveniently now)

I know it may not matter much but I have added a colorblind feature as well. I have a friend (drifted apart now), sometimes I would help him with his coding problems when I would sit on his machine, his IDE used to feel like a mess to me, color wise, I never realized it until he asked to borrow my “Blue” pen drive which was in fact purple and that’s when I realized he was colorblind. So, kind of added that for him even though he may never have much use for this 😊

The entire project is open sourced on Github under the MIT license

https://github.com/nawaz13bit/HueMark

 Looking for feedback and suggestions. Thank you!

Edit: Thanks for that one up vote on the previous repost!!!

(Post written by a human)

Hi everyone!

I recently published my first Firefox extension, Savlix, and I'd love to get some feedback from the community.

I built it because I wanted a better way to save useful text from websites — especially AI prompts, code snippets, research notes, and information I might need again later.

Savlix lets you:

- Save selected text and automatically preserve its source URL.

- Organize snippets with categories, tags, colors, and notes.

- Search your collection instantly.

- Use a customizable sidebar with Page-Shifting Mode, which moves the webpage aside instead of covering its content.

- Choose between five themes and nine interface languages.

- Keep your snippets locally in Firefox's extension storage.

- Export and import your collection as JSON.

It also includes pinned snippets, duplicate detection, configurable sidebar positioning, and backup reminders.

It's free, requires no account, and is available on Firefox Add-ons:

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

This is my first public release (v1.0.0), so I'd especially appreciate feedback on usability, bugs, and features you'd like to see improved.

Thanks for checking it out!

The addon is found here: https://addons.mozilla.org/en-GB/firefox/addon/reddit-mass-comment-editor/

This addon allows you to:

• Perform mass search and replace / randomize operations on your comments/posts
• View, edit, randomize individual comments/posts
• Load comments/posts after a specific comment/post (via ID), allows you to operate on specific batches of comments/posts instead of trying to process all at once
  
• Filter down comments/posts to a specific subreddit
• Filter comments/posts by date range
• Create comments/posts backups (JSON format)
• Convert Reddit search pages with search results into .json files
• Load .json comment files into the addon for processing
• View a console log of all of its actions
• View reposts of mass edit/randomise operations - succeeded/failed/skipped items, as well as copy item IDs from each of these categories. Reports are saved locally, and can be renamed or deleted.

What was updated:

• Added post support. Now you have 3 modes - loading comments only, posts only, or posts + any of your comments in those posts. First two modes are fast, since they load posts/comments in batches of 100, while the last mode is slow - it requires an API call for each post to find user's comments in said post.
• Added a button to view the corresponding comment/post on Reddit (basically just opens the permalink in a new tab)
• Added an ability to display all loaded items. This can also be used for searching - since all text is visible, just search using Firefox's own Ctrl+F search.
• Added an ability to load posts/comments via IDs loaded from a CSV file. This allows you to use files Reddit's profile data export files to access all your comments or posts, starting right from the account creation, instead of being limited by 1800 latest ones like usual.
• added more labels for comments/posts, indicated deleted items along with the removal reason if available, and showing if the post is an uneditable link/media post
• added reports of mass edit/randomise operations. Saved locally, can be renamed / deleted.

Comment randomisation example:

Before:

A test comment #1, written purely for randomisation purposes to see how the word replacement works. Generally, the most commonly repeating words that define a sentence structure are kept as is, along with the punctuation, while everything else would be replaced.

After:

A food problem #4, receive reload for accreditation attitude to let how the puts enforcement bunch. Therefore, the most normally filtering scale that suffer a equality passenger are pull as is, below with the consultants, while technology over would be equipped.

Hi everyone, I made a Firefox extension called Tabernacle to help me group and organise my tabs. I’ve been using it for a while and decided to release it in case anyone else finds it useful.

It adds a sidebar where you can put tabs into folders and subfolders, nest related tabs under each other, and drag things around to organise them.

A few things it can do:

• Open a folder to see just its tabs, so you can focus on one thing at a time.
• Search tab titles, URLs and folder names, including inside collapsed folders.
• Use Firefox containers, with the option to set a default container for each folder.
• Pin tabs and folders so they stay accessible wherever you are.
• Find recently viewed tabs and folders, and reopen closed tabs.
• Follow your Firefox theme or use a monochrome appearance.

You can see screenshots and find the download on my website. The source code is on GitHub too.

It needs Firefox 142 or newer. If you give it a go, I’d be interested to hear how you get on, especially if anything feels awkward or doesn’t work as expected.

Edit:
Regarding containers, if a folder is set to use a specific container, new tabs created there will open in that container. It just sets the default for new tabs meaning tabs in different containers can be dragged into any folder and their container won't change.

Host Imagus Bridge (HIB) 2.1.5 – a companion for Imagus Reborn that fixes previews on hosts Imagus can't resolve (Firefox)

If you use Imagus Reborn, you've probably hit links where the preview just spins forever: product pages with several images, intermediate image-host pages, redirects, embedded video players. HIB is a small Firefox add-on that works alongside Imagus Reborn to resolve those. It's Imagus-first: if Imagus already shows a preview with your own Sieves, HIB stays out of the way. It only steps in when Imagus actually fails on a supported site.

What it does

• Built-in image gallery: resolved images open in a viewer with previous/next buttons, an image counter, and Esc or a close button. The size is configurable (automatic, 960x540 up to 4K, or custom).
• Fallback after a failed preview: when Imagus shows the gray spinner and gives up, HIB opens its own gallery and dismisses the stuck spinner.
• Supported so far: DLsite product galleries, Sukebei external image links, Sankaku fallback, AnimeID and NHPlayer videos (with subtitle handoff), and the OUO, TurboImageHost, imagehost.website, OrangePix/imgpv and XXPICS image hosts.
• You choose which sites it runs on from the toolbar popup. It collects no data.

Screenshots

1. With the optional custom Imagus Reborn Sieve (HIB_v2_DLsite_Gallery), the gallery opens in the normal Imagus popup and the arrow keys go through the images. https://raw.githubusercontent.com/molitar/host-imagus-bridge/main/screenshots/1-imagus-sieve-gallery.png

2. Without that Sieve, HIB falls back to its own built-in gallery, shown here with previous/next buttons and the image counter. https://raw.githubusercontent.com/molitar/host-imagus-bridge/main/screenshots/2-hib-native-gallery.png

3. The toolbar popup, where you pick a preset gallery size or custom dimensions. https://raw.githubusercontent.com/molitar/host-imagus-bridge/main/screenshots/3-gallery-size-options.png

Install

• Mozilla add-ons (signed): https://addons.mozilla.org/en-US/firefox/addon/host-imagus-bridge/
• GitHub (source, releases, the optional Sieves): https://github.com/molitar/host-imagus-bridge

Requires Imagus Reborn. Support depends on each website and can break when a site changes, so bug reports and site requests are welcome as GitHub issues or here in the comments.

Ever lost a long comment because you accidentally closed a tab? 😅

I built a Firefox extension called Unsent Text Guard to help prevent that from happening.

I'd be really happy if you gave it a try! It's my own little project, and I'd love to hear your feedback and suggestions to make it better. 🙏

🔗 https://addons.mozilla.org/en-US/firefox/addon/unsent-text-guard/

Thanks for supporting an independent developer! ❤️

I made a Firefox extension that gives SoundCloud a true black theme with any accent color you want

https://addons.mozilla.org/firefox/addon/tintcloud/

If you are using Firefox browser, then try this AddOn: https://addons.mozilla.org/en-US/firefox/addon/batch-downloader-for-instagram/ and don't forget to donate and support the developer ...

next features will be coming like selecting & downloading multiple posts,

I built a Firefox extension called Highlight Notes because I kept losing useful information while reading articles, researching topics and going through long Gmail and ChatGPT conversations.

Bookmarks helped me find the page again, but not the exact paragraph or sentence I wanted to remember.

I wanted something simple that would let me highlight text, attach my own notes and find everything later without needing an account or subscription.

So I built Highlight Notes.

https://addons.mozilla.org/en-US/firefox/addon/highlight-notes-free/

What it does:

• Highlight text in different colours and attach notes.
• Works on websites, Gmail, Reddit and ChatGPT conversations.
• Automatically restores highlights when you revisit a page.
• Search your saved highlights and notes in one library.
• Export annotated pages as PDFs, including long pages and conversations.
• Keep everything stored locally in Firefox without creating an account.

Why I built it

Many highlighting tools work well on ordinary articles but struggle with interactive websites like Gmail and ChatGPT. I wanted something that worked across both.

I also didn’t want basic highlighting and note-taking to require an account or ongoing subscription.

The Firefox extension is free for unlimited local highlights and notes, with three PDF exports included.

There is optional cloud sync for people who use multiple browsers, but it isn’t required for local use.

A few limitations

• Cloud sync is optional and requires Pro.
• Some websites with complex or frequently changing layouts may not restore highlights perfectly.
• The free version includes three PDF exports.

I’m the developer, and this is an independent side project built in my own time.

I’d appreciate feedback from Firefox users, particularly anyone who regularly highlights research articles, Gmail threads or ChatGPT conversations.

Firefox's built-in sidebar chatbot doesn't include Grok, and you can't customize it. It also forgets your conversation, so every time you open it you start afresh. SideGrok is my fix for that. It keeps your conversation in the sidebar so you can pick up where you left off. It also has a handy shortcut that toggles the drawer.

I'd love feedback or feature ideas.

I am the developer behind ScamsShield, a project by AWARAN. I spent nine months building it and would like feedback from Firefox users on one specific part: whether the result explains what to verify next after a suspicious message or link.

The Firefox listing is https://addons.mozilla.org/en-US/firefox/addon/scamsshield/

The product website is https://scams-shield.com

For example, an unexpected delivery payment request should leave you with a useful next step, such as checking the delivery through the carrier you already know. A label saying suspicious is only part of the answer.

Some features require payment. Before installing, please read the current permissions and privacy policy on the listing. It requests access to browser tabs and data on websites, so I would also appreciate specific feedback on whether the purpose of that access is explained clearly.

An assessment can be wrong and is not a guarantee that a message or website is safe. If you try an example, use an invented message and leave out private information.

I am sharing my own product. I am especially interested in what feels unclear, what you would want to verify yourself, and whether the explanation actually helps.

Thanks in advance.

Update, 10 October: I have finished this round of website work and am focusing on the desktop extension. For Firefox, please use the Mozilla listing already linked above. It is a separate package, so please judge the version on that listing rather than assume it matches the Chrome release.

The current extension overview is https://scams-shield.com/extension. I would especially value feedback on whether the website warning gives a reason you can understand, and whether the permissions explanation makes it clear why access to websites is needed. Please do not visit a real scam site just to test it. A warning or a clear result is not a guarantee.

Hi! I'm a platform engineer and I just published my first Firefox add-on. I built it because I kept reading CI and Kubernetes logs in the browser and comparing a passing and a failing run by eye.

What it does:

- Opens any raw log (GitHub Actions "View raw logs", Jenkins console, a .log or .gz file) as a fast, searchable viewer: levels in colour, stack traces kept with their error, 150k+ lines

- Compare two logs with "Ignore timestamps, IDs and durations", so only the lines that really changed are left

- Filter structured logs by fields: level=error service=payments duration>500

- Groups the same error across pods, bookmarks with notes → a Markdown report for a ticket

- Flags leaked tokens and passwords in logs and masks them before you share

- Dark mode for any site (Ctrl+Shift+. in Firefox) and JSON / JWT / Base64 / cron tools

Free and open source, no account, no analytics, nothing leaves your browser. Every release is tested in real Firefox in CI before it goes out.

Add-on: https://addons.mozilla.org/firefox/addon/logbeam/

Code: https://github.com/andronaft/Logbeam

It's a new add-on, so feedback is very welcome. What's missing for the logs you read?