Bug description
Screenshots/recordings
No response
Superset version
master / latest-dev
Python version
3.9
Node version
16
Browser
Chrome
Additional context
No response
Checklist
- [x] I have searched Superset docs and Slack and didn't find a solution to my problem.
- [x] I have searched the GitHub issue tracker and didn't find a similar bug report.
- [x] 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.
Comment From: dosubot[bot]
The most common cause of fatal errors when saving dashboards in Superset master/latest-dev is a version mismatch between the frontend and backend, especially around the handling of color and theme fields like map_label_colors and shared_label_colors. If these fields are missing or have the wrong type in the dashboard metadata, the backend will reject the save with a 400/422 error, which surfaces as a generic "fatal error" in the UI. This can also happen if recent changes to dashboard or theme handling introduced stricter validation or new required fields that older dashboards or charts don't satisfy (example, example).
To troubleshoot:
- Double-check that both your frontend and backend are running the exact same Superset version. Even a small mismatch can cause these payload/schema errors.
- Inspect the dashboard and chart metadata for invalid or missing map_label_colors or shared_label_colors. If you see errors about "Unknown field" or "Not a valid mapping type", try editing the affected chart, go to the "Advanced" section, and remove or correct the problematic color fields (details).
- If you recently imported dashboards or upgraded, re-save any charts that are part of the dashboard to ensure their metadata and query context are up to date (details).
- Check your backend logs for validation errors or stacktraces when the save fails—these often include the exact field or schema problem.
If the issue persists, sharing the backend error log or the failing dashboard/chart metadata will help pinpoint the root cause. Recent changes to theme import/export logic could also affect dashboard saves if themes are involved (PR #34850).
To reply, just mention @dosu.
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Comment From: msyavuz
A bit more context on this would be nice, especially some reproduction steps.