JupyterLab 3 end of maintenance

The JupyterLab Council has agreed to an important change to JupyterLab’s version lifecycle. Each major version of JupyterLab will now receive updates until one year after the following major version’s first release. JupyterLab 4.0.0 was released on May 15, 2023, so JupyterLab 3 will reach its end of maintenance date on May 15, 2024, anywhere on Earth. To help us make this transition, fixes for critical issues will still be backported until December 31, 2024. If you are still running JupyterLab 3, we strongly encourage you to upgrade to JupyterLab 4 as soon as possible.

This represents a change from JupyterLab’s previous policy, by which we supported two major versions of JupyterLab at a time, and which would have obligated us to continue supporting JupyterLab 3 until JupyterLab 5.0.0 became generally available. We decided to make this change to let developers, contributors, and users focus their attention on the newest major version, JupyterLab 4. Maintaining multiple major versions requires additional time and effort, which could instead be put towards making the current version better for all users. Recent releases on the 3.6.x branches have included mainly security fixes and maintenance fixes, not new features.

We recognize that there are many users still using JupyterLab 3, having downloaded it directly from package repositories or using it as distributed by a commercial vendor. We strongly encourage all users and vendors to upgrade to Lab 4 as soon as possible. If this is not possible, out of acknowledgement for the short notice of this announcement, we will consider pull requests addressing critical issues against the 3.6.x branch through December 31, 2024, anywhere on Earth, provided that they meet all of the following requirements:

1. The fix addresses a critical issue: a security vulnerability, data loss, or another issue of very high severity.
2. The fix includes tests, is reasonably small and low in complexity, and the author communicates actively with maintainers who review their work.
3. The fix is approved by a JupyterLab maintainer.

The JupyterLab team recognizes that a few regressions from JupyterLab 3 were present in JupyterLab 4.0.0; some of them are still open. Project Jupyter is driven by volunteers, community contributors, and support from individual and corporate users. We thank our community for their patience and we encourage our contributors to help us resolve bugs that block users from upgrading to the newer version. The JupyterLab maintainers are committing to review any pull requests submitted to address regressions as a priority over pull requests

We want to hear from you! If you have questions or comments about this new version lifecycle, please leave them below, or join the conversation on the Jupyter Community Forum. We also welcome discussion about the change at our weekly JupyterLab meetings, which are held every Wednesday at 09:00 US Pacific (17:00 UTC as of today, 16:00 UTC starting on March 10, 2024).

Thank you for using JupyterLab and for being a part of our great global community!