Browser Extension

The Motrix browser extension turns “download this” into a single click: instead of the browser’s own download manager, the file goes to Motrix — with your login session carried along, so even files behind a sign-in download fine. It also handles things browsers can’t, like assembling streaming video into a single file.

Install Motrix Extension#

Motrix Extension is now available for Chrome, Microsoft Edge, and Firefox. Use it with Motrix 2:

• Chrome: Install from the Chrome Web Store.
• Microsoft Edge: Install from Microsoft Edge Add-ons.
• Firefox: Install from Firefox Add-ons.

For development builds, see the build and manual loading instructions in the extension repository.

Setting it up#

1. Install the extension using the matching browser link above, then manually launch Motrix 2 on this computer. Review the first-launch terms and, if you agree, accept them and continue to the main window before pairing.
2. Allow the connection in Motrix. The switch “Send downloads from browser extensions” in Settings → Integration → Browser extensions is on by default; Motrix registers the browser-side connector automatically for all three browsers.
3. Start pairing. Open the extension and click Pair. The desktop edition discovers Motrix on this computer automatically; choose the correct instance if it finds more than one.
4. Enter the pairing code. Motrix shows the browser, extension identity, and an eight-character code. Confirm that you started the request, then enter that code in the extension. Deny a suspicious request in Motrix; an untouched request expires automatically.

Approved browsers appear under Connected extensions, each with a Last active time and a Disconnect button — disconnecting is also how you force a fresh pairing.

If local pairing fails#

First, open Motrix manually and complete first-launch setup. If the terms screen is still open, review and accept the terms if you agree, then wait for the main window before retrying in the extension. Motrix initializes its services after this step, so installing the app alone is not enough for local pairing.

If you installed Motrix through Homebrew and pairing still fails, try the Motrix 2 package from the official GitHub Releases. Open the newly installed app, complete first-launch setup, and retry pairing.

If pairing still fails, click Diagnose in the extension’s connection error panel. Copy the report with the small copy button at its top right and include it when reporting the issue. For an unpacked development extension, also check that its current extension ID is trusted in Motrix and included in the Native Host allowlist.

Connect to Motrix Server#

A remote Server does not use the desktop app’s native-messaging discovery path. Its administrator must first upgrade to a Server build with remote MBP1 support and explicitly enable the remote browser-extension routes. The Server startup log prints the exact WS/WSS address to enter. Add that address in the extension’s Server settings and start pairing. The Motrix web UI displays an eight-character code; enter it in the extension to authenticate.

See Motrix Server (Docker) for the settings, the WS/HTTP risk acknowledgement for NAS deployments, and WSS reverse-proxy paths.

What you can send#

• Regular files — the extension replays the browser’s headers and cookies, so authenticated downloads work without any manual cookie copying.
• Streaming video (HLS/DASH) — Motrix downloads the segments, then combines audio and video with FFmpeg into one file. FFmpeg is managed under Settings → Integration → Media tools (Motrix uses the bundled copy, a custom path, or the system installation — the card shows which).
• Magnet links — handed straight to the torrent workflow.

Clicking send twice by accident is fine — duplicate requests for the same download are ignored.

If a handoff fails#

The extension surfaces Motrix’s actual reason, in plain words:

Message	What it means
“Live streams cannot be downloaded”	The video is a live broadcast, not a finished file
“DRM-protected content cannot be downloaded”	The content is encrypted with DRM — Motrix will not bypass it
“Session expired — refresh the page in your browser and try again”	Your login on the site ran out mid-handoff
“ffmpeg failed while combining audio and video”	The final merge failed — check Media tools for FFmpeg status
“Resume failed; restart the download”	The server refused to continue a partial file

Trusted extensions (advanced)#

Under Trusted extensions you can authorize a third-party extension to talk to Motrix: click Add extension, paste its extension ID, and pick the browser (Chrome/Edge or Firefox). As the settings screen itself notes, most people never need this — the official extension is trusted out of the box.