Matrix Instant Messaging

The network hosts its own instant messaging, based on Matrix 🡕. Discussions, photo and file sharing, audio and video calls : everything stays with us, on our server.

What is Matrix?

Matrix is a messaging system comparable to WhatsApp or Telegram, with three key differences :

• Private: messages are stored on the home server, not with a web giant.
• Encrypted: conversations are end-to-end encrypted by default.
• Open: you can choose your application (client) among several 🡕, on computer or phone.

Conversations are organized into rooms : one room per topic, per family, per project… and direct messages between two people.

Connecting

My Matrix ID is built from my usual account : @prenom:domain.tld. No new password to remember, authentication uses the network’s single sign-on (same as for other services, see Managing my account).

1. On computer: I open https://element.domain.tld in my browser, click Sign in, and authenticate with my network account.

2. On phone: I install the Element app (Android or iPhone). At startup, I choose “Other server” and enter matrix.domain.tld, then authenticate the same way.

3. On first connection, Element prompts me to verify my session and back up my encryption keys. I follow the instructions : this will let me read my old messages on a new device.

The home domain name

Throughout this page, domain.tld refers to the network’s domain name. If in doubt, ask the administrator.

Element X, the new app

Element X 🡕 is the next generation of the mobile app : faster, smoother, and a lightning-fast connection via QR code, without typing anything.

1. I install Element X (Android or iPhone).

2. On a device where I’m already logged in (Element on desktop, for example) : Settings → Sessions → « Link a new device », a QR code appears.

3. In Element X, I choose « Sign in with a QR code » and scan it. Done : my rooms and my messages are there.

Without a QR code, the regular login also works : I enter the matrix.domain.tld server and authenticate with my network account.

Another new feature : the page https://matrix.domain.tld/account shows my connected devices. Handy for closing a session left open on a forgotten device.

Depending on the network configuration

Element X and this account page require next-generation authentication, a recent server option. If the connection fails, ask the administrator whether it is enabled.

Making audio or video calls

In a room, the call button starts an audio or video conversation. Between two or more people : other room members see the call in progress and can join it with a click, no invitation needed.

It works from Element X, from Element on desktop and from the web client, including between different applications.

The classic Element app stays out of it

The old mobile application can only make two-person calls between two old applications. It cannot even see calls started from Element X : the two applications use different calling technologies, and no server setting changes anything about it.

Two ways to work around it :

• Best : install Element X, and everyone calls each other.
• Troubleshooting, without installing anything : open https://element.domain.tld in the phone browser and sign in. The web client can join Element X calls.

If calling is not offered

A ” Calling is not supported ” message means the server does not have the group-calling component yet. This is an administration setting : report it to the network administrator.

Bridges to WhatsApp, Telegram, and others

A bridge connects Matrix to an external messaging service. Once the bridge is activated, my WhatsApp, Telegram, or Messenger conversations appear in Element as regular rooms: I read and reply from Element, while my contacts see no difference.

These bridges are built on the mautrix 🡕 project, the reference in the field. Each bridge has its own official documentation page, linked in the sections below.

Each bridge is operated by a bot: a special contact I send commands to. The principle is the same for all:

1. In Element, I start a direct conversation with the bridge bot (for example @whatsappbot:domain.tld).

2. I send it login and follow its instructions (scan a QR code, provide my phone number…).

3. That’s it: my conversations appear gradually. Each user connects their own account, without interfering with other users on the network.

What about privacy?

The bridge decrypts messages to relay them from one world to another: this is unavoidable, but everything happens on our server, not in some unknown cloud. If in doubt about a command, send help to the bot.

WhatsApp

The WhatsApp bridge connects as a linked device, exactly like WhatsApp Web. Simple and reliable.

1. Start a direct conversation with @whatsappbot:domain.tld and send it login qr.

2. On the phone: WhatsApp → Settings → Linked devices → Link a device, then scan the QR code displayed in Element.

Keep the phone within reach

Like WhatsApp Web, the phone must reconnect from time to time: beyond two weeks offline, the linked device is disconnected and you need to repeat the process. Alternative without scanning: login phone displays a code to enter on the phone.

📖 Official WhatsApp bridge documentation 🡕

Signal

The Signal bridge connects as an additional linked device, without touching the phone’s existing connection.

1. Start a direct conversation with @signalbot:domain.tld and send it login.

2. On the phone: Signal → Settings → Linked devices → Add, then scan the QR code displayed in Element.

Message history

When connecting, Signal may offer to transfer conversation history. Otherwise, rooms fill up as new messages come in.

📖 Official Signal bridge documentation 🡕

Telegram

The Telegram bridge connects with my phone number, like another Telegram client.

1. Start a direct conversation with @telegrambot:domain.tld and send it login phone +33612345678 (number in international format).

2. Enter the verification code sent by Telegram, then, if my account has a “two-step” password, that password.

Where does the code arrive?

Telegram does not send the code by SMS: it displays it in an already open Telegram session (phone or desktop). So you need an already connected Telegram client. Alternative: login qr to scan a QR code.

📖 Official Telegram bridge documentation 🡕

Messenger (Facebook)

The Messenger bridge connects by reusing the cookies of a session open in a browser. This is the most technical connection of all.

1. Start a direct conversation with @messengerbot:domain.tld and send it login.

2. Log in to messenger.com in a private window, then follow the bot’s instructions to hand over the session cookies.

Tricky step

Retrieving cookies requires using the browser’s developer tools. If in doubt, ask the administrator for help. Enabling two-factor authentication on the Facebook account limits blocks.

📖 Official Meta (Messenger) bridge documentation 🡕

Discord

The Discord bridge connects with a simple QR code scan.

1. Start a direct conversation with @discordbot:domain.tld and send it login-qr.

2. Scan the QR code with the Discord app on your phone (Settings → Scan QR code).

Optional bridge

The Discord bridge is not enabled by default. If it does not respond, ask the administrator to enable it.

📖 Official Discord bridge documentation 🡕

Useful commands

Send to the bridge’s bot, in its direct conversation :

Command	Effect
help	List available commands
login	Connect my account
logout	Disconnect my account from the bridge

Troubleshooting

Almost every email problem comes from the phone, not the server. Android puts apps to sleep to save battery, and a sleeping app does not ring.

The phone does not ring, or rings too late

This is the number one cause. The server notifies the phone within one or two seconds; it is the phone that processes the alert late, sometimes after about thirty seconds, sometimes never.

1. Lift the battery restriction : Settings → Apps → Element → Battery → Unrestricted. The “Optimized” mode is not enough.

2. Remove Element from apps that are put to sleep : on Samsung phones, Settings → Battery → Background usage limits. Remove Element from the “Sleeping apps” and “Deep sleeping apps” lists, then disable “Put unused apps to sleep”.

3. Allow full-screen notifications : Settings → Apps → Element → Notifications → Full-screen notifications. Without this permission, Android 14 and later replace the incoming-call screen with a silent notification.

4. Check the “Calls” channel : still in Element’s notifications, this channel must have a sound and the right to ignore Do Not Disturb mode.

The only test that counts

Lock the phone, leave it aside for a quarter of an hour, then get called. A test done on a phone that is on and active proves nothing : it is at rest that Android delays everything.

No notification arrives

If even ordinary messages go unnoticed, check in this order :

Check	How to do it
The app has been opened at least once	It only announces itself to the server at its first launch, after installation just as after reinstallation
The room is not muted	Long press on the room, then Notifications
“Do Not Disturb” mode is off	Android settings
The session is still open	https://matrix.domain.tld/account lists my connected devices

As a last resort, log out and then log back in in the app : it announces itself to the server again at the next start.

Which app to install?

The two mobile apps do not handle calls the same way.

	Element X	Classic Element
Messages and bridges	Yes	Yes
Two-person calls	With Element X and the web client	Between classic apps
Group calls	Yes	No
QR-code login	Yes	No

For everyone to call each other without asking questions, the simplest thing remains to install Element X everywhere. The detail of the incompatibility and troubleshooting without installing anything are described above, in Call in audio or video.

What to report to the administrator

If nothing works, these four pieces of information save them a lot of time :

• The exact time of the missed message or call, with the time zone.
• The name of the person at the other end.
• The app used on each side (Element X or Classic Element).
• The state of the phone : locked or in hand, wifi or mobile data.

Why specify the time zone?

The server may be hosted in a country other than mine. A time given without its time zone sends the administrator looking in the wrong place in the server logs.

See also

• Matrix in DNF : bridge architecture
• Matrix: operations guide : deployment and administration