Element (formerly known as Vector and Riot) is a Matrix web client built using the Matrix React SDK.
Element has several tiers of support for different environments:
The easiest way to test Element is to just use the hosted copy at https://app.element.io.
develop branch is continuously deployed to https://develop.element.io
for those who like living dangerously.
To host your own copy of Element, the quickest bet is to use a pre-built released version of Element:
element-x.x.xdirectory to an appropriate name
config.jsonand modifying it. See the configuration docs for details.
Releases are signed using gpg and the OpenPGP standard, and can be checked against the public key located at https://packages.riot.im/element-release-key.asc.
Note that for the security of your chats will need to serve Element over HTTPS. Major browsers also do not allow you to use VoIP/video chats over HTTP, as WebRTC is only usable over HTTPS. There are some exceptions like when using localhost, which is considered a secure context and thus allowed.
To install Element as a desktop application, see Running as a desktop app below.
We do not recommend running Element from the same domain name as your Matrix homeserver. The reason is the risk of XSS (cross-site-scripting) vulnerabilities that could occur if someone caused Element to load and render malicious user generated content from a Matrix API which then had trusted access to Element (or other apps) due to sharing the same domain.
We have put some coarse mitigations into place to try to protect against this situation, but it's still not good practice to do it in the first place. See https://github.com/vector-im/element-web/issues/1977 for more details.
Unless you have special requirements, you will want to add the following to your web server configuration when hosting Element Web:
X-Frame-Options: SAMEORIGINheader, to prevent Element Web from being framed and protect from clickjacking.
frame-ancestors 'self'directive to your
Content-Security-Policyheader, as the modern replacement for
X-Frame-Options(though both should be included since not all browsers support it yet, see this).
X-Content-Type-Options: nosniffheader, to disable MIME sniffing.
X-XSS-Protection: 1; mode=block;header, for basic XSS protection in legacy browsers.
If you are using nginx, this would look something like the following:
add_header X-Frame-Options SAMEORIGIN; add_header X-Content-Type-Options nosniff; add_header X-XSS-Protection "1; mode=block"; add_header Content-Security-Policy "frame-ancestors 'self'";
For Apache, the configuration looks like:
Header set X-Frame-Options SAMEORIGIN Header set X-Content-Type-Options nosniff Header set X-XSS-Protection "1; mode=block" Header set Content-Security-Policy "frame-ancestors 'self'"
Note: In case you are already setting a
elsewhere, you should modify it to include the
instead of adding that last line.
Element is a modular webapp built with modern ES6 and uses a Node.js build system. Ensure you have the latest LTS version of Node.js installed.
yarn instead of
npm is recommended. Please see the Yarn install
guide if you do not have it already.
node.jsso that your
nodeis at least the current recommended LTS.
yarnif not present already.
git clone https://github.com/vector-im/element-web.git.
config.jsonand modifying it. See the configuration docs for details.
yarn distto build a tarball to deploy. Untaring this file will give a version-specific directory containing all the files that need to go on your web server.
yarn dist is not supported on Windows, so Windows users can run
which will build all the necessary files into the
webapp directory. The version of Element
will not appear in Settings without using the dist script. You can then mount the
webapp directory on your web server to actually serve up the app, which is
entirely static content.
Element can also be run as a desktop app, wrapped in Electron. You can download a pre-built version from https://element.io/get-started or, if you prefer, build it yourself.
To build it yourself, follow the instructions at vector-im/element-desktop.
Many thanks to @aviraldg for the initial work on the Electron integration.
Other options for running as a desktop app:
yarn global add nativefier nativefier https://app.element.io/
The configuration docs show how to override the desktop app's default settings if desired.
The Docker image can be used to serve element-web as a web server. The easiest way to use it is to use the prebuilt image:
docker run -p 80:80 vectorim/element-web
To supply your own custom
config.json, map a volume to
/app/config.json. For example,
if your custom config was located at
/etc/element-web/config.json then your Docker command
docker run -p 80:80 -v /etc/element-web/config.json:/app/config.json vectorim/element-web
To build the image yourself:
git clone https://github.com/vector-im/element-web.git element-web cd element-web git checkout master docker build .
If you're building a custom branch, or want to use the develop branch, check out the appropriate element-web branch and then run:
docker build -t \ --build-arg USE_CUSTOM_SDKS=true \ --build-arg REACT_SDK_REPO="https://github.com/matrix-org/matrix-react-sdk.git" \ --build-arg REACT_SDK_BRANCH="develop" \ --build-arg JS_SDK_REPO="https://github.com/matrix-org/matrix-js-sdk.git" \ --build-arg JS_SDK_BRANCH="develop" \ .
The provided element-web docker image can also be run from within a Kubernetes cluster. See the Kubernetes example for more details.
Element supports a variety of settings to configure default servers, behaviour, themes, etc. See the configuration docs for more details.
Some features of Element may be enabled by flags in the
Labs section of the settings.
Some of these features are described in labs.md.
Element requires the following URLs not to be cached, when/if you are serving Element from your own webserver:
/config.*.json /i18n /home /sites /index.html
We also recommend that you force browsers to re-validate any cached copy of Element on page load by configuring your
webserver to return
Cache-Control: no-cache for
/. This ensures the browser will fetch a new version of Element on
the next page load after it's been deployed. Note that this is already configured for you in the nginx config of our
Before attempting to develop on Element you must read the developer guide
also defines the design, architecture and style for Element too.
Read the Choosing an issue page for some guidance about where to start. Before starting work on a feature, it's best to ensure your plan aligns well with our vision for Element. Please chat with the team in #element-dev:matrix.org before you start so we can ensure it's something we'd be willing to merge.
You should also familiarise yourself with the "Here be Dragons" guide to the tame & not-so-tame dragons (gotchas) which exist in the codebase.
The idea of Element is to be a relatively lightweight "skin" of customisations on
top of the underlying
matrix-react-sdk provides both the
higher and lower level React components useful for building Matrix communication
apps using React.
Please note that Element is intended to run correctly without access to the public internet. So please don't depend on resources (JS libs, CSS, images, fonts) hosted by external CDNs or servers but instead please package all dependencies into Element itself.
CSS hot-reload is available as an opt-in development feature. You can enable it
by defining a
CSS_HOT_RELOAD environment variable, in a
.env file in the root
of the repository. See
.env.example for documentation and an example.
Much of the functionality in Element is actually in the
matrix-js-sdk modules. It is possible to set these up in a way that makes it
easy to track the
develop branches in git and to make local changes without
having to manually rebuild each time.
First clone and build
git clone https://github.com/matrix-org/matrix-js-sdk.git pushd matrix-js-sdk yarn link yarn install popd
Then similarly with
git clone https://github.com/matrix-org/matrix-react-sdk.git pushd matrix-react-sdk yarn link yarn link matrix-js-sdk yarn install popd
Clone the repo and switch to the
git clone https://github.com/vector-im/element-web.git cd element-web
Configure the app by copying
modifying it. See the configuration docs for details.
Finally, build and start Element itself:
yarn link matrix-js-sdk yarn link matrix-react-sdk yarn install yarn start
Wait a few seconds for the initial build to finish; you should see something like:
[element-js] <s> [webpack.Progress] 100% [element-js] [element-js] ℹ ｢wdm｣: 1840 modules [element-js] ℹ ｢wdm｣: Compiled successfully.
Remember, the command will not terminate since it runs the web server and rebuilds source files when they change. This development server also disables caching, so do NOT use it in production.
Open http://127.0.0.1:8080/ in your browser to see your newly built Element.
Note: The build script uses inotify by default on Linux to monitor directories
for changes. If the inotify limits are too low your build will fail silently or with
Error: EMFILE: too many open files. To avoid these issues, we recommend a watch limit
of at least
128M and instance limit around
To set a new inotify watch and instance limit, execute:
sudo sysctl fs.inotify.max_user_watches=131072 sudo sysctl fs.inotify.max_user_instances=512 sudo sysctl -p
If you wish, you can make the new limits permanent, by executing:
echo fs.inotify.max_user_watches=131072 | sudo tee -a /etc/sysctl.conf echo fs.inotify.max_user_instances=512 | sudo tee -a /etc/sysctl.conf sudo sysctl -p
When you make changes to
matrix-js-sdk they should be
automatically picked up by webpack and built.
If any of these steps error with,
file table overflow, you are probably on a mac
which has a very low limit on max open files. Run
ulimit -Sn 1024 and try again.
You'll need to do this in each new terminal you open before building Element.
There are a number of application-level tests in the
tests directory; these
are designed to run with Jest and JSDOM. To run them
See matrix-react-sdk for how to run the end-to-end tests.
To add a new translation, head to the translating doc.
For a developer guide, see the translating dev doc.
Issues are triaged by community members and the Web App Team, following the triage process.
We use issue labels to sort all incoming issues.