Firefox ESR (Extended Support Release) is a version of Firefox designed for organizations that need extended support for mass deployments. This container provides Firefox ESR with unsigned extension support enabled for development and testing purposes.
- 🔥 Firefox ESR - Extended Support Release with long-term stability
- 🔓 Unsigned Extensions - Pre-configured to allow installation of unsigned extensions
- 🏗️ Multi-Platform - Supports both AMD64 and ARM64 architectures
- 🚀 Auto-Build - GitHub Actions workflow for automated builds
- 🌐 Web-Based - Accessible via web browser using KasmVNC
This image utilizes the docker manifest for multi-platform awareness. More information is available from docker here.
Simply pulling carefulcomputer/firefox-esr:latest should retrieve the correct image for your architecture, but you can also pull specific arch images via tags.
The architectures supported by this image are:
| Architecture | Available | Tag |
|---|---|---|
| x86-64 | ✅ | amd64-<version tag> |
| arm64 | ✅ | arm64v8-<version tag> |
| armhf | ❌ |
The application can be accessed at:
Modern GUI desktop apps have issues with the latest Docker and syscall compatibility, you can use Docker with the --security-opt seccomp=unconfined setting to allow these syscalls on hosts with older Kernels or libseccomp
This image comes pre-configured with the following Firefox preferences to allow unsigned extensions:
xpinstall.signatures.required = false- Allows installation of unsigned extensionsextensions.langpacks.signatures.required = false- Allows unsigned language packs
This image also enables experimental extension features for advanced development and testing:
extensions.experiments.enabled = true- Enables experimental extension APIsextensions.webextensions.restrictedDomains = ""- Removes domain restrictions for WebExtensionsdevtools.chrome.enabled = true- Enables advanced developer toolsdevtools.debugger.remote-enabled = true- Enables remote debugging capabilitiesextensions.webextensions.keepStorageOnUninstall = true- Preserves extension storage on uninstallextensions.webextensions.keepUuidOnUninstall = true- Preserves extension UUID on uninstall
Warning
Security Notice: Allowing unsigned extensions and experimental features reduces security as these extensions haven't been reviewed by Mozilla and may have access to additional APIs. Only install extensions from trusted sources and use experimental features in development environments.
You can install unsigned extensions by:
- Drag and Drop: Download the
.xpifile and drag it into Firefox - File Installation: Go to
about:addons→ Click the gear icon → "Install Add-on From File" - Developer Mode: Load temporary extensions from
about:debugging
Warning
Do not put this on the Internet if you do not know what you are doing.
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, 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 container is based on Docker Baseimage KasmVNC which means there are additional environment variables and run configurations to enable or disable specific functionality.
| Variable | Description |
|---|---|
| CUSTOM_PORT | Internal port the container listens on for http if it needs to be swapped from the default 3000. |
| CUSTOM_HTTPS_PORT | Internal port the container listens on for https if it needs to be swapped from the default 3001. |
| CUSTOM_USER | HTTP Basic auth username, abc is default. |
| PASSWORD | HTTP Basic auth password, abc is default. If unset there will be no auth |
| SUBFOLDER | Subfolder for the application if running a subfolder reverse proxy, need both slashes IE /subfolder/ |
| TITLE | The page title displayed on the web browser, default "KasmVNC Client". |
| FM_HOME | This is the home directory (landing) for the file manager, default "/config". |
| START_DOCKER | If set to false a container with privilege will not automatically start the DinD Docker setup. |
| DRINODE | If mounting in /dev/dri for DRI3 GPU Acceleration allows you to specify the device to use IE /dev/dri/renderD128 |
| DISABLE_IPV6 | If set to true or any value this will disable IPv6 |
| LC_ALL | Set the Language for the container to run as IE fr_FR.UTF-8 ar_AE.UTF-8 |
| NO_DECOR | If set the application will run without window borders in openbox for use as a PWA. |
| NO_FULL | Do not autmatically fullscreen applications when using openbox. |
| Variable | Description |
|---|---|
--privileged |
Will start a Docker in Docker (DinD) setup inside the container to use docker in an isolated environment. For increased performance mount the Docker directory inside the container to the host IE -v /home/user/docker-data:/var/lib/docker. |
-v /var/run/docker.sock:/var/run/docker.sock |
Mount in the host level Docker socket to either interact with it via CLI or use Docker enabled applications. |
--device /dev/dri:/dev/dri |
Mount a GPU into the container, this can be used in conjunction with the DRINODE environment variable to leverage a host video card for GPU accelerated applications. Only Open Source drivers are supported IE (Intel,AMDGPU,Radeon,ATI,Nouveau) |
The environment variable LC_ALL can be used to start this container in a different language than English simply pass for example to launch the Desktop session in French LC_ALL=fr_FR.UTF-8. Some languages like Chinese, Japanese, or Korean will be missing fonts needed to render properly known as cjk fonts, but others may exist and not be installed inside the container depending on what underlying distribution you are running. We only ensure fonts for Latin characters are present. Fonts can be installed with a mod on startup.
To install cjk fonts on startup as an example pass the environment variables (Alpine base):
-e DOCKER_MODS=linuxserver/mods:universal-package-install
-e INSTALL_PACKAGES=fonts-noto-cjk
-e LC_ALL=zh_CN.UTF-8
The web interface has the option for "IME Input Mode" in Settings which will allow non english characters to be used from a non en_US keyboard on the client. Once enabled it will perform the same as a local Linux installation set to your locale.
For accelerated apps or games, render devices can be mounted into the container and leveraged by applications using:
--device /dev/dri:/dev/dri
This feature only supports Open Source GPU drivers:
| Driver | Description |
|---|---|
| Intel | i965 and i915 drivers for Intel iGPU chipsets |
| AMD | AMDGPU, Radeon, and ATI drivers for AMD dedicated or APU chipsets |
| NVIDIA | nouveau2 drivers only, closed source NVIDIA drivers lack DRI3 support |
The DRINODE environment variable can be used to point to a specific GPU.
Up to date information can be found here
Nvidia support is not compatible with Alpine based images as Alpine lacks Nvidia drivers
Nvidia support is available by leveraging Zink for OpenGL support. This can be enabled with the following run flags:
| Variable | Description |
|---|---|
| --gpus all | This can be filtered down but for most setups this will pass the one Nvidia GPU on the system |
| --runtime nvidia | Specify the Nvidia runtime which mounts drivers and tools in from the host |
The compose syntax is slightly different for this as you will need to set nvidia as the default runtime:
sudo nvidia-ctk runtime configure --runtime=docker --set-as-default
sudo service docker restart
And to assign the GPU in compose:
services:
firefox:
image: lscr.io/linuxserver/firefox:latest
deploy:
resources:
reservations:
devices:
- driver: nvidia
count: 1
capabilities: [compute,video,graphics,utility]
If you run system native installations of software IE sudo apt-get install filezilla and then upgrade or destroy/re-create the container that software will be removed and the container will be at a clean state. For some users that will be acceptable and they can update their system packages as well using system native commands like apt-get upgrade. If you want Docker to handle upgrading the container and retain your applications and settings we have created proot-apps which allow portable applications to be installed to persistent storage in the user's $HOME directory and they will work in a confined Docker environment out of the box. These applications and their settings will persist upgrades of the base container and can be mounted into different flavors of KasmVNC based containers on the fly. This can be achieved from the command line with:
proot-apps install filezilla
PRoot Apps is included in all KasmVNC based containers, a list of linuxserver.io supported applications is located HERE.
It is possible to install extra packages during container start using universal-package-install. It might increase starting time significantly. PRoot is preferred.
environment:
- DOCKER_MODS=linuxserver/mods:universal-package-install
- INSTALL_PACKAGES=libfuse2|git|gdbTo help you get started creating a container from this image you can either use docker-compose or the docker cli.
Note
Unless a parameter is flaged as 'optional', it is mandatory and a value must be provided.
docker-compose (recommended, click here for more info)
---
services:
firefox-esr:
image: carefulcomputer/firefox-esr:latest
container_name: firefox-esr
security_opt:
- seccomp:unconfined #optional
environment:
- PUID=1000
- PGID=1000
- TZ=Etc/UTC
- FIREFOX_CLI=https://www.linuxserver.io/ #optional
volumes:
- /path/to/config:/config
ports:
- 3000:3000
- 3001:3001
shm_size: "1gb"
restart: unless-stoppeddocker cli (click here for more info)
docker run -d \
--name=firefox-esr \
--security-opt seccomp=unconfined `#optional` \
-e PUID=1000 \
-e PGID=1000 \
-e TZ=Etc/UTC \
-e FIREFOX_CLI=https://www.linuxserver.io/ `#optional` \
-p 3000:3000 \
-p 3001:3001 \
-v /path/to/config:/config \
--shm-size="1gb" \
--restart unless-stopped \
carefulcomputer/firefox-esr:latestContainers 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.
| Parameter | Function |
|---|---|
-p 3000:3000 |
Firefox ESR desktop gui. |
-p 3001:3001 |
Firefox ESR desktop gui HTTPS. |
-e PUID=1000 |
for UserID - see below for explanation |
-e PGID=1000 |
for GroupID - see below for explanation |
-e TZ=Etc/UTC |
specify a timezone to use, see this list. |
-e FIREFOX_CLI=https://www.linuxserver.io/ |
Specify one or multiple Firefox ESR CLI flags, this string will be passed to the application in full. |
-v /config |
Users home directory in the container, stores local files and settings |
--shm-size= |
This is needed for any modern website to function like youtube. |
--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. |
You can set any environment variable from a file by using a special prepend FILE__.
As an example:
-e FILE__MYVAR=/run/secrets/mysecretvariableWill set the environment variable MYVAR based on the contents of the /run/secrets/mysecretvariable file.
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 before asking for support.
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.
In this instance PUID=1000 and PGID=1000, to find yours use id your_user as below:
id your_userExample output:
uid=1000(your_user) gid=1000(your_user) groups=1000(your_user)
-
Shell access whilst the container is running:
docker exec -it firefox-esr /bin/bash -
To monitor the logs of the container in realtime:
docker logs -f firefox-esr
-
Container version number:
docker inspect -f '{{ index .Config.Labels "build_version" }}' firefox-esr -
Image version number:
docker inspect -f '{{ index .Config.Labels "build_version" }}' carefulcomputer/firefox-esr:latest
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 section above to see if it is recommended for the image.
Below are the instructions for updating containers:
-
Update images:
-
All images:
docker-compose pull
-
Single image:
docker-compose pull firefox-esr
-
-
Update containers:
-
All containers:
docker-compose up -d
-
Single container:
docker-compose up -d firefox-esr
-
-
You can also remove the old dangling images:
docker image prune
-
Update the image:
docker pull carefulcomputer/firefox-esr:latest
-
Stop the running container:
docker stop firefox-esr
-
Delete the container:
docker rm firefox-esr
-
Recreate a new container with the same docker run parameters as instructed above (if mapped correctly to a host folder, your
/configfolder and settings will be preserved) -
You can also remove the old dangling images:
docker image prune
Tip
We recommend Diun for update notifications. Other tools that automatically update containers unattended are not recommended or supported.
If you want to make local modifications to these images for development purposes or just to customize the logic:
git clone https://github.com/carefulcomputer/docker-firefox-dev.git
cd docker-firefox-dev
docker build \
--no-cache \
--pull \
-t carefulcomputer/firefox-esr:latest .The ARM variants can be built on x86_64 hardware and vice versa using lscr.io/linuxserver/qemu-static
docker run --rm --privileged lscr.io/linuxserver/qemu-static --resetOnce registered you can define the dockerfile to use with -f Dockerfile.aarch64.
This project is based on the excellent work by the LinuxServer.io team. The original Firefox container and KasmVNC base image foundation provided the solid groundwork that made this customized Firefox ESR container possible.
Original Project: linuxserver/docker-firefox
Base Image: linuxserver/docker-baseimage-kasmvnc
Special thanks to LinuxServer.io for:
- Creating the KasmVNC base image infrastructure
- Providing excellent containerization practices and patterns
- Maintaining high-quality Docker containers for the community
- Their commitment to open source and detailed documentation
If you find this container useful, consider supporting the original LinuxServer.io project:
- 01.01.25: - Switch to Firefox ESR with unsigned extension support. Add GitHub Actions workflow for automated builds.
- Changed from Firefox regular to Firefox ESR
- Added support for unsigned extensions (
xpinstall.signatures.required = false) - Added multi-platform Docker builds (AMD64 + ARM64)
- Updated Firefox settings path for ESR installation
- 25.09.24: - Rebase to Ubuntu Noble.
- 23.05.24: - Rebase to Alpine 3.20.
- 13.02.24: - Add ability to pass CLI args to Firefox.
- 10.02.24: - Update Readme with new env vars and ingest proper PWA icon.
- 01.01.24: - Rebase to Alpine 3.19.
- 13.05.23: - Rebase to Alpine 3.18.
- 18.03.23: - Rebase to KasmVNC base image.
- 21.10.22: - Rebase to Alpine 3.16, migrate to s6v3.
- 23.12.21: - Rebase to Alpine 3.15, stop using ESR.
- 26.09.21: - Rebase to Alpine 3.14.
- 19.04.21: - Initial release.