description: "[Firefox](https://www.mozilla.org/en-US/firefox/) Browser, also known as Mozilla Firefox or simply Firefox, is a free and open-source web browser developed by the Mozilla Foundation and its subsidiary, the Mozilla Corporation. Firefox uses the Gecko layout engine to render web pages, which implements current and anticipated web standards."
[Firefox](https://www.mozilla.org/en-US/firefox/) Browser, also known as Mozilla Firefox or simply Firefox, is a free and open-source web browser developed by the Mozilla Foundation and its subsidiary, the Mozilla Corporation. Firefox uses the Gecko layout engine to render web pages, which implements current and anticipated web standards.
We utilise the docker manifest for multi-platform awareness. More information is available from docker [here](https://distribution.github.io/distribution/spec/manifest-v2-2/#manifest-list) and our announcement [here](https://blog.linuxserver.io/2019/02/21/the-lsio-pipeline-project/).
Simply pulling `lscr.io/linuxserver/firefox:latest` should retrieve the correct image for your arch, but you can also pull specific arch images via tags.
This image provides various versions that are available via tags. Please read the descriptions carefully and exercise caution when using unstable or development tags.
| Tag | Available | Description |
| :----: | :----: |--- |
| latest | ✅ | Latest releases using the selkies base |
| kasm | ✅ | Latest releases using the kasmvnc base |
By default this container has no authentication and the optional environment variables `CUSTOM_USER` and `PASSWORD` to enable basic http auth via the embedded NGINX server should only be used to locally secure the container from unwanted access on a local network. If exposing this to the Internet we recommend putting it behind a reverse proxy, such as [SWAG](https://github.com/linuxserver/docker-swag), and ensuring a secure authentication solution is in place. From the web interface a terminal can be launched and it is configured for passwordless sudo, so anyone with access to it can install and run whatever they want along with probing your local network.
This image uses a self-signed certificate by default. This naturally means the scheme is `https`.
If you are using a reverse proxy which validates certificates, you need to [disable this check for the container](https://docs.linuxserver.io/faq#strict-proxy).
Containers are configured using parameters passed at runtime (such as those above). These parameters are separated by a colon and indicate `<external>:<internal>` respectively. For example, `-p 8080:80` would expose port `80` from inside the container to be accessible from the host's IP on port `8080` outside the container.
| `--security-opt seccomp=unconfined` | For Docker Engine only, many modern gui apps need this to function on older hosts as syscalls are unknown to Docker. |
For all of our images we provide the ability to override the default umask settings for services started within the containers using the optional `-e UMASK=022` setting.
Keep in mind umask is not chmod it subtracts from permissions based on it's value it does not add. Please read up [here](https://en.wikipedia.org/wiki/Umask) before asking for support.
## User / Group Identifiers
When using volumes (`-v` flags), permissions issues can arise between the host OS and the container, we avoid this issue by allowing you to specify the user `PUID` and group `PGID`.
Ensure any volume directories on the host are owned by the same user you specify and any permissions issues will vanish like magic.
[](https://mods.linuxserver.io/?mod=firefox "view available mods for this container.") [](https://mods.linuxserver.io/?mod=universal "view available universal mods.")
We publish various [Docker Mods](https://github.com/linuxserver/docker-mods) to enable additional functionality within the containers. The list of Mods available for this image (if any) as well as universal mods that can be applied to any one of our images can be accessed via the dynamic badges above.
Most of our images are static, versioned, and require an image update and container recreation to update the app inside. With some exceptions (noted in the relevant readme.md), we do not recommend or support updating apps inside the container. Please consult the [Application Setup](#application-setup) section above to see if it is recommended for the image.
Below are the instructions for updating containers:
### Via Docker Compose
* Update images:
* All images:
```bash
docker-compose pull
```
* Single image:
```bash
docker-compose pull firefox
```
* Update containers:
* All containers:
```bash
docker-compose up -d
```
* Single container:
```bash
docker-compose up -d firefox
```
* You can also remove the old dangling images:
```bash
docker image prune
```
### Via Docker Run
* Update the image:
```bash
docker pull lscr.io/linuxserver/firefox:latest
```
* Stop the running container:
```bash
docker stop firefox
```
* Delete the container:
```bash
docker rm firefox
```
* Recreate a new container with the same docker run parameters as instructed above (if mapped correctly to a host folder, your `/config` folder and settings will be preserved)
We recommend [Diun](https://crazymax.dev/diun/) for update notifications. Other tools that automatically update containers unattended are not recommended or supported.
## Building locally
If you want to make local modifications to these images for development purposes or just to customize the logic:
