Online Tools for Communicating with Other Rebels

This book describes the tools you can use to communicate and collaborate with other rebels. In particular it focuses on Mattermost, UK Forums and UK Cloud, as well as the Hub that links them all together. If there is any information missing from these pages please either contact the Digital Discussions Application Team on Mattermost or email For support on the Hub, Mattermost, Forums or Cloud, ask in Hub Help Desk channel on Mattermost. For information about local group (and region/nation/UK) email lists see Action Network for XR on shelf 02


This document is a quick guide to get you started with using XR's online communication tools for the first time.

In this guide, you will:

  1. Set up an account on the Hub.
  2. Log in to Mattermost and send a message to your XR group.
  3. Find out where to find more information.

Note: This guide assumes that you will be using a desktop computer, although if you are using a smartphone the steps should be the same. You can use either your smartphone's browser app (e.g. Chrome or Safari), or you can download the Mattermost app. For a guide on using the online tools with a smartphone, please read this page.

Note: If you have any trouble with this guide, please contact your XR group's group admin. If you don't know who this is or if your group doesn't have one, then please email

1. Joining the Hub hub.png

What is the Hub?

The Hub is the key to accessing the other online tools. It does two main things:

  1. When you join the Hub you will automatically have accounts created for you (with the same username and password) on all of the main tools that we use (including Mattermost).
  2. You are encouraged to create a username that is recognisably related to you - some rebels are happy to use their Local Group as part of their username – like tom-bangor – while others may align with their Working Group – like rose-creatives. However, should you wish to remain anonymous, you are free to choose a username that totally conceals your identity.
  3. The Hub acts as a phone directory – you can use the Hub to find and contact other groups.

For more information on the Hub, please read this guide.

How do I join the Hub?

To sign up to the Hub:

  1. Ask the group admin of your XR group to send you an email invite to the Hub.
  2. Open the invite and click on the link (you may need to check your spam folder). This will open a webpage containing a form that looks like this: g1himage1.png
  3. Fill in the form with your name (this is visible to other users, so you can use a nickname if you like) and password and then click Confirm.

This video takes you through the steps outlined above.

Any problems?

If you are encountering any issues, read this page for information on how to fix the most common problems, as well as where to go to ask for help.

2. First steps on Mattermost Mattermost-icon-small.png

What is Mattermost?

Mattermost is a secure chat application that your group can use to communicate instead of using a program like WhatsApp, Signal or Telegram. It can be used both on a desktop computer and a smartphone.

The main advantage Mattermost has over other chat tools is that it is MUCH easier to get in contact with other rebels. Most groups in XR UK are already signed up to Mattermost and it is simple to find and message them. Also, Mattermost is used by XR Global so you can even get in touch with rebels across the world!

Getting access

  1. Navigate to Mattermost in your browser. You can do this by either clicking on the Mattermost button from the Hub home page or by clicking on this link.
  2. Enter your username and password set up when signing up to the Hub.
  3. Go to your email inbox, open the email you just received from XR Global (you may need to check your spam folder) and click Verify Email.
  4. Go back to Mattermost (a new window should have been opened), re-enter your password, and click Sign in.
  5. Bookmark this page. This will make it much easier to find in the future.

For a video guide through these steps, see here.

Mattermost basics

Once you have successfully logged in to Mattermost, you should see a screen that looks like this:


On the left-hand side (5) are the public and private Channels that you are in. When clicking on the Channels, note that the messages shown on the right (14) will change.

Below the Channels are your Direct Messages (6). These are private conversations that you can have with up to six other people.

At the far-left of the screen (1), you may see two or more blocks. These are Mattermost Teams and can be used to group Channels together. If you navigate between the different Teams, notice how the Channels shown change.

For a more detailed guide to using Mattermost, see this page on the Rebel Toolkit.

Sending your first message

To message your group for the first time:

  1. Find the correct Channel to post a message in. To do, this click through your Channels and Teams until you find a Channel with the same (or similar) name as your group.
  2. Write a hello message in the box at the bottom of the screen (15).
  3. Hit Enter to send the message.

3. Next steps

If you are interested in learning more, there are more advanced guides on both the Hub and Mattermost as well as XR UK's other tools. In particular, you might want to look at the guides for UK Forums and UK Cloud.

We also strongly encourage you to read our Online Behaviour Guide.

Lastly, if you have any trouble at all with these tools, please contact your group admin. They are there to help!

If you need support with:

please join one of the weekly sessions:

Mondays 17:30–18:00 (quick questions)

Thursdays 18:30–19:30 (longer training)

Join Zoom Meeting

Meeting ID: 895 2855 8324 Passcode: 278766

Or post queries or problems in the Hub Help Desk channel on Mattermost.

Extinction Rebellion UK Privacy Policy

Extinction Rebellion UK Terms of Service

User Guides

User Guides


Read this document to get familiar with Mattermost. It is used to communicate with XR groups as well as have 1-to-1 conversations.

If you need support with:

Please join one of the weekly sessions:

Mondays 17:30-18:00 (quick questions)

Thursdays 18:30-19:30 (longer training)

Join Zoom Meeting

Meeting ID: 895 2855 8324 Passcode: 278766

First Steps

Getting Access

Before you can access Mattermost you first need to sign up to the XR UK Communications Hub. For instructions on how to do this, please read this guide.

Once you are on the Hub, there are a few ways to access Mattermost:

  1. Click on the Mattermost icon from the Comms Hub main page.

  1. Type into your browser and hit Enter.

Once this is done, we recommend adding the page to your bookmarks/favourites so it's easier to find in future.

Note: Mattermost is also available as an app so you can install it to your smartphone or tablet. Please read this document for instructions on how to do this.

Landing Page

When you have logged in to Mattermost, you will see a screen that looks a lot like this:


Note that we have added numbers to the screenshot and we will refer to this image throughout the document.

Basic Navigation

Watch this 5 minute video for an introduction on finding your way around Mattermost.


Teams in Mattermost are basically collections of Channels. Teams appear on the far left of your screen (1). Click to switch between them.

You will be added to the UK Team by default but your group might use other Teams — you will see these too.

Checking who else is in my Team

To see the other members of a Team, click on the Main Menu (3) and select View Members.

Joining other Teams

UK Circles with their own Team can be contacted via their Reception Channel in UK Team.

To join a public Team, click on the + sign next to your list of Teams (1) and then click "Browse Channels". This will bring up a list of all the other XR public Teams you are able to join, including for other countries. Click on one of the list of Teams to add yourself.

If you want to be added to a private Team (e.g. for your local group), you will need to speak to a Group Admin/Tech Champion who will be able to send you an invite.

Leaving a Team

To leave a Team, open the Main Menu (3), and then select the option Leave Team.

Note that once you have left a Team, if you want to re-join at any point, you will have to join (or be invited to) all the Channels you belong(ed) to previously.


Channels are just another name for group chats. Every local group/working group set up on the Hub will have several of these Channels that you will be added to if you are part of that group.

Note: For a walkthrough of Channels, you can watch the Finding and Joining Channels video (4 mins).

Type of Channels

IRCChannel-public-private-icons.PNG Most Channels are public, so anyone in the Team can join them. They have a picture of the globe next to them. Some Channels are private, by invitation only, and they have a padlock next to them.

Joining Channels

To join a public Channel, either click in Find Channel and search, or click the + button to browse Channels on the left (4). This will bring up a list of all of the public Channels in your Team. Click on any of these in the list to add yourself.

To join a private Channel, you should ask someone already in that Channel to add you. You could also post a message in that group's reception Channel asking to be added.

Leaving a Channel

To leave a Channel, click its name at the top of the screen (not where it appears lower down on the left) and then select the option Leave Channel. Alternatively, if you hover over the Channel lower down on the left, three dots will appear next to it — from that menu, select Leave Channel.

Muting Channels

You can mute Channels if you want to stop receiving notifications from it but don't want to leave. To do this, click the Channel heading (at the top of the screen), or hover over the Channel lower down on the left and click the three dots, and then click Mute Channel. You can also set whether you want to be notified if someone uses @all or @channel in Settings (11).

Default Channels

Every Team has two default Channels that you will be added to when you are added to the team:

Very Important: Please do not rename these default Channels as it will cause a lot of confusion.

Note: It is not possible to leave the Town Square Channel. If you want to stop receiving notifications, you should mute the Channel instead.

Sorting Channels

If you hover over the Channels header on the lower left (5), by clicking on the three dots that then appear, you can sort your Channels in one of three ways:

In addition, you can Create New Category which enables you to sort Channels into groups that suit you, e.g. relating to particular projects or areas of interest. Once you have created your categories, you can drag and drop Channels between them.

Contacting other groups

All XR UK groups on Mattermost have a public 'Reception' Channel in the UK Team, and their members will be added to them by default (you will probably be in some yourself). This lets rebels from other groups find and speak to them.

To join someone else's reception Channel, go to the UK Team, click Find Channel or + (4), to search or browse for the Channel you want to join and then click Join. The Channel will then appear in your Channels list.

Creating Channels

Important: You should not create public Channels from inside Mattermost. Instead, please get your Group Admin/Tech Champion to do this for you using the Hub.

To create a private Channel:

  1. Click on the + sign next to the Main Menu (3)
  2. Select 'Create New Channel'
  3. Enter a name for the new Channel (and optional Purpose and Header), ensuring that 'Private' is selected
  4. Click Create Channel

Channel headers (7)

Underneath the Channel name at the top of the page is the Channel header. It is a useful place to put information about what the Channel is for and to store some useful links (e.g. your group's Forum or your regular Zoom meetings).

To see all the info, click on the Channel name:


then click on View Info.

If you want to change what is written in the header, click on Edit Channel Header. If you want to add links to this section, the process is the same as here. Please confirm with your Group Admin before making any change to the Header.

Sending Messages (15)

You can write messages by typing in the box at the bottom of the screen. To send them hit Enter. The message will be sent to the Channel or Direct Message you are currently in.

Alerting people to messages

If you want a particular person to read a message you are sending, you can tag them by writing '@' followed by their username (e.g. @xrukadmin). This will send them a notification.

Important: You can also use @all or @channel to notify everyone in a Channel but please use this responsibly as for larger groups it is rarely appropriate and may annoy people.

Sending Direct Messages (6)

To send someone a Direct Message (instead of posting in a Channel):

  1. Click the + sign to the right of the heading DIRECT MESSAGES to the left of the screen (6)
  2. Select the users you want to message (up to a maximum of 6)
  3. Write and send your message

All of the Direct Message conversations that you have had will appear below the DIRECT MESSAGES heading to make it easier to contact them again. Next to each name, an icon shows whether they are online or not. Clicking on a username will display your Direct Message history with that user. Users you do not need to contact regularly can be removed from this list by pressing the cross to the right of their name.

Sorting your Direct Messages

Much like with Channels, Direct Messages can be sorted alphabetically or most recent first. You can also choose how many to show (all, 10, 15...). To change these settings hover over DIRECT MESSAGES then click the three dots to the right of it.

Replying to messages

It is possible to reply to messages posted in Channels or Direct Messages using 'threads'. These are helpful if you are having multiple conversations at once so people don't get confused about which messages are related to which discussion. To reply to a message in a thread click on the Reply icon:


You can access your threaded messages on the Mattermost homepage (18). Clicking 'Threads' will bring up all threads you are participating in, and you can post any replies or catch up on messages more easily.


Note: For a full explanation, watch the threading messages video (5 mins).

Reacting to messages

To add a reaction (e.g. a thumbs up or heart icon) to a message click on the Add Reaction icon:


To post a reaction to a message, click on the Emoticon icon on the bottom right-hand side (17).


Searching for messages (10)

Use the search box to find messages and replies that match the search terms entered. All Channels that you are a member of in the current Team are searched.

Note: For a full explanation, watch the Searching for messages video (3 mins).

Saving messages

You can click on the 'save' icon (like a bookmark) next to a message to save it for later, then bring up all your saved messages by clicking on the 'Saved posts' icon at the top right of the screen (12).

Note: For a full explanation, watch the Saving messages video (3 mins).

To add a picture, click on the paperclip icon on the bottom right of the screen (16). To add a nicely formatted link to your message, write the text you want to show in square brackets immediately followed by the link URL in round brackets. For example:

Check out this fantastic [guide to Mattermost](!

will look like:

Check out this fantastic guide to Mattermost!

when sent.

Other formatting tips

Here are a few simple tips on formatting messages:


Copying messages

It can be difficult to copy messages in order to share them in multiple Channels without losing the formatting and any links. Currently, the only way this is to:

  1. Open Settings (underneath 2)
  2. On the sidebar, click Advanced
  3. Set Enable Post Formatting to Off
  4. Copy and paste the messages that you want to share
  5. Return to Account Settings -> Advanced and set Enable Post Formatting back to On

Video Calls (8) 5JPBig-blue-button-icon.png

If you are in a Direct Message chat, clicking the 'Big Blue Button' will start a video call between you and the person (or people) in that chat; if you are in a Channel, it will open a video chat link for anyone in that Channel to join, using Big Blue Button. This posts a link for everyone to click on to join the call.

Rebel Compass (9)

Rebel Compass is a trusted guide through XR Global Support's digital services and infrastructure. Clicking this icon will take you to a resource page including plaforms, videos, documents, trainings, events, etc.

Notification settings

Note: For a walkthrough of all the content in this section, watch the Notifications (5 mins) and Acccount Settings (4 mins) videos.

So that you don't miss any important messages, it's strongly recommended that you adjust your notification settings. This will also make sure you aren't overwhelmed by huge numbers of irrelevant notifications.

To modify the notification settings in Mattermost, open Settings (underneath 2), which brings up the following: