Turn on Orbit in GitLab Duo by default

What does this MR do and why?

Removes the Use Orbit in GitLab Duo checkbox from User settings > Preferences. Orbit in GitLab Duo is now on by default for every user who can use Orbit, as decided in the 2026-10-02 sync. Users still choose each Orbit feature: Agentic Chat, Orbit Agent, Other Foundational Agents, and Custom Agents. A stored opt-out is ignored. There is no data migration, so a revert gives users back their old choice.

Closes gitlab-org/orbit/knowledge-graph#1360 (closed)

Who gets Orbit in GitLab Duo

Instance	Before	After
GitLab.com	Users who selected the checkbox	Direct members of a paid top-level group that has Orbit on
Self-managed and Dedicated	The user's checkbox. The admin setting gives the default value.	All users, when the admin setting is on and the instance has the :orbit license

In all cases, the Orbit service must be configured.

References

• Draft MR that this MR is cut from: !259468 (closed)
• Admin area > Orbit page, which shows the same admin setting: !261333 (merged)
• Dashboard alert for a missing default group, which links to the #orbit-default-group anchor: !260936 (merged)

What changes for users

• The checkbox is gone. The four features always show, and they are on by default.
• To stop Orbit in GitLab Duo, a user clears the four features.
• GitLab team members can now turn off the Orbit Agent. Before, it stayed on until they saved the preferences form.
• The Billable Orbit namespace field has the anchor #orbit-default-group, so the dashboard alert links to it.
• Members of only a subgroup do not get Orbit in GitLab Duo. They have no default group to assign usage to. A spec pins this.

What changes for administrators

• Enable Orbit in GitLab Duo by default is now Turn on Orbit in GitLab Duo. It turns Orbit in GitLab Duo on or off for the whole instance. The setting key stays orbit_dap_enabled_by_default.
• When the setting is off, the Orbit section does not show in Preferences.
• Orbit in GitLab Duo now also checks the :orbit license. Before, only the Preferences section checked it.

Screenshots or screen recordings

Before	After

How to set up and validate locally

GitLab.com:

1. Use a GDK in GitLab.com mode (GITLAB_SIMULATE_SAAS=1) with Orbit configured.
2. Sign in as a direct member of a paid top-level group that has Orbit on, and go to http://127.0.0.1:3000/-/profile/preferences. The Orbit section shows the four features and no checkbox.
3. Sign in as a user with no such group. The Orbit section does not show, and Duo Agentic Chat gets no Orbit tools.

Self-managed:

1. Use a self-managed GDK with an Orbit license.
2. Go to http://127.0.0.1:3000/admin/orbit and clear Turn on Orbit in GitLab Duo.
3. Go to http://127.0.0.1:3000/-/profile/preferences. The Orbit section does not show.

MR acceptance checklist

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