Video downloader extension for Firefox

The Firefox build is published and signed by Mozilla on addons.mozilla.org, so it installs in one click and updates itself like any official add-on.

What it detects

HLS (.m3u8) and DASH (.mpd) streams, direct MP4 files, and also images, PDFs, documents and archives on the page.

Pick the quality before downloading; the file is rebuilt as MP4 without re-encoding, audio in sync.

What differs on Firefox — worth knowing up front

Firefox does not implement the File System Access API. That has two concrete consequences, and they belong here rather than in a disappointed review: you cannot pick a folder per file type through a picker — subfolders inside Downloads are used instead — and there is no side panel or own window as on the Chromium build.

Everything else — detection, qualities, MP3, trimming, the size filter — works the same.

Large downloads

Without that API to write to disk, Firefox assembles the file in memory before saving. In practice downloads of over 1.5 GB have completed without trouble, but this is where the Firefox build has the least headroom compared to Chrome or Edge.

If you routinely pull whole films and have both browsers, the Chromium build will give you fewer surprises.

Step by step

1. Install from addons.mozilla.orgMozilla-signed add-on; it updates automatically.
2. Open the video and play itDetection starts the moment the player requests the content.
3. Click the add-on iconWhat was detected appears with its estimated size.
4. Pick a quality and downloadFiles go to your Downloads folder, in per-type subfolders if you configure them.

Frequently asked questions

← YDownloadNow