Bug description

I have an error when generating permalinks in Apache Superset version 6

Context and Observations

Dashboards created directly in v6

Permalink generation works normally, regardless of their level of complexity :

• Without tabs.
• With tabs (1 level).
• With nested tabs (multiple levels).

Dashboards imported from v5:

Systematic error, but only on one dashboard when generating a permalink, with the following message:

{
"message": "{'activeTabs': {2: ['Field may not be null.']}}"
}

Consequence

After this error, permalink generation stopped working for all dashboards, including those that previously worked.

Temporary solution

Refreshing the page (F5) restores functionality for dashboards not affected by the error.
However, the imported dashboard remains blocked.

Additional elements

dashboard_export_20260610T120033.zip

The problematic dashboard consists only of static elements (charts, datasets, and database connections were deliberately removed to isolate the problem).

Attachment

Export of the concerned dashboard (file attached to this message).

Screenshots/recordings

Superset version

master / latest-dev

Python version

3.9

Node version

16

Browser

Chrome

Additional context

No response

Checklist

• I have searched Superset docs and Slack and didn't find a solution to my problem.
• I have searched the GitHub issue tracker and didn't find a similar bug report.
• I have checked Superset's logs for errors and if I found a relevant Python stacktrace, I included it here as text in the "additional context" section.