Lightning's end of life (EOL) FAQ - acquia/lightning GitHub Wiki

So you're a Lightning user and you've heard that Lightning will reach its end-of-life (EOL) November 2021. We've tried to make the path forward as straightforward and painless and possible; this page aims to answer some questions you may have.

If you're an Acquia customer, see also the official version of this FAQ.

Does this mean I can't update to Drupal 9??

You can absolutely update to Drupal 9! Lightning 5, released in summer of 2020, runs on Drupal 9. If you're currently using Lightning, you can update to Lightning 5, which will also update you to Drupal 9.

So what does "end-of-life with Drupal 8" mean?

It means that, when Drupal 8 reaches its EOL in November 2021, we're going to stop releasing updates for the Lightning profile, including security updates. We won't be updating any version of Lightning 3, 4, or 5. (Note that this applies only to the installation profile; the individual Lightning components will continue to receive security updates and bug fixes.)

How should I prepare for the Lightning profile's EOL?

You should ask your development team to uninstall the Lightning profile, using the process documented here. The process will remove your site's dependency on Lightning without affecting your site's look or functionality in any way. Once it's done, you'll be able to update Drupal core and contributed modules without waiting for a new version of Lightning.

The uninstaller utility is already available in the most recent version of Lightning, so if you'd prefer to uninstall it now, we encourage you to do that. See the documentation for more information.

Do I need to update to Lightning 5 (Drupal 9) in order to uninstall?

No! The uninstaller is available in the latest versions of Lightning 3, 4, and 5. You just need to update Lightning using your normal process to the latest minor version. If you're on Lightning 3.4, for example, you don't need to update to Lightning 4 or 5 to do the uninstall procedure.

But wait, I'm using some of the features from Lightning's modules!

Uninstalling the Lightning profile will NOT remove or deactivate any of those features because they are provided by Lightning components (e.g., Lightning Workflow, Lightning Media, etc.), which are not being EOLed at this time. They'll continue to operate on your site, just like all your other installed modules, and they'll receive bug fixes and security updates until at least Drupal 9's end-of-life in 2023. You can keep using and updating these Lightning modules as if they were any other module (because they are normal modules). You don't need the "full Lightning package" for them to work.

Can I just switch from Lightning to Acquia CMS?

No direct migration path is planned. For now, it's not possible to migrate directly from Lightning to Acquia CMS.

What happens if I still haven't uninstalled Lightning by the EOL deadline?

Nothing. Your site will continue to work. But you may start to miss updates to modules or Drupal core, including security updates, so you will have a higher potential for security issues.

Does uninstalling Lightning involve code changes?

Yes, but in most cases the changes are minimal, and most of them can be handled automatically by our uninstall utility. See the documentation for more information.