With Endless OS 4, we introduced a long-term support version of Endless OS. This is primarily intended for partners who need to support a large number of Endless OS users themselves, and prefer a slower-moving baseline on which to develop their own documentation, end-user training, and tools.
By default, most new installations of Endless OS 4, and systems upgraded from older versions of Endless OS, will automatically update to Endless OS 5, and beyond as further versions are released. Systems must be specifically configured to remain on Endless OS 4, as documented below.
We plan to support Endless OS 4 for approximately 2–3 years after its release in November 2021.
Endless OS 4 is based on Debian Bullseye. We anticipate that the next stable version of Debian, codenamed Bookworm, will be released in 2023–2024, and around this time we will release a new LTS version, Endless OS 6, based on Debian Bookworm. At this time, ongoing support for Endless OS 4 will end. Systems following the Endless OS 4 LTS will not automatically upgrade to Endless OS 6 when it becomes available, though we hope to provide an optional upgrade path from Endless OS 4 to Endless OS 6.
We will offer technical support for Endless OS 4 throughout its lifetime, via our dedicated partner support channels, and via best-effort assistance on the Community Forums, without requesting or requiring the end user to update to any newer major version of Endless OS as part of the support process.
Only Endless OS itself – meaning the desktop and built-in apps and utilities like App Center, Files and Help – are covered by this long-term support policy. A complete list of built-in apps can be provided on request.
Most apps on Endless OS, including Kolibri and all web browsers, are provided using Flatpak. These apps, which can be installed and removed through the App Center, will receive updates with new functionality and user interface changes, even on Endless OS 4 systems. Automatic app updates can be disabled, if desired, in the App Center. Specific Flatpak apps can be pinned to the currently-installed version using the flatpak mask command; consult the flatpak-mask(1) documentation for further details.
According to demand from our partners and users, we intend to occasionally release new versions in the Endless OS 4 series (4.0.1, 4.0.2, etc) for the following types of changes:
If an Endless OS 4 update includes new functionality to support specific deployment needs, we will strive to ensure this functionality is additive and implemented in a way that has only a minor visible impact, if any, on the user interface for other users.
In this way, existing documentation and training materials for the OS will remain valid throughout the lifetime of Endless OS 4.
We encourage all users of the long-term support branch to install such updates as they become available.
We do not currently publish any prebuilt, generic images that will install and remain on Endless OS 4. Please let us know on the Community Forums if you have a particular need for such images.
We anticipate that most deployments of the long-term support branch of Endless OS 4 will use installation images supplied by Endless OS Foundation, preconfigured to use the LTS branch, or custom images built with the open-source Endless OS Image Builder.
When building a custom image, use the following configuration to configure the image to use (and remain on) the Endless OS 4 LTS branch:
[ostree]
stable_branch = eos4
On an already-installed system currently running Endless OS 4, run the following commands in a Terminal window:
sudo systemctl mask --runtime eos-updater
sudo ostree admin switch eos:os/eos/amd64/eos4
Then restart the computer.
This command is only supported on a system which is already running Endless OS 4. Downgrades from Endless OS 5 are not supported.