Werk #19828: Fix crash when saving "Read only mode for configuration" form

Component

Setup

Title

Fix crash when saving "Read only mode for configuration" form

Date

Jun 25, 2026

Level

Trivial Change

Class

Bug Fix

Compatibility

Compatible - no manual interaction needed

Checkmk versions & editions

3.0.0b1 Not yet released	Checkmk Community, Checkmk Pro, Checkmk Ultimate, Checkmk Cloud, Checkmk Ultimate MT
2.5.0p9 Not yet released	Checkmk Community, Checkmk Pro, Checkmk Ultimate, Checkmk Cloud, Checkmk Ultimate MT

When saving the form in Setup > General > Read-only mode for configuration, Checkmk would crash with the following message.

Internal Error: UserSelection to disk transform expected UserId, got '...'

This werk fixes the underlying bug allowing you to save as expected.

No migrations are required.