Kibana error for theme validation

I just noticed that my kibana log is full of 'failed validation' errors... like zillions of them:

 log   [11:21:26.836] [warning][ui-settings-service] Ignore invalid UiSettings value. Error: [validation [theme:version]]: types that failed validation:
- [validation [theme:version].0]: expected value to equal [v7]
- [validation [theme:version].1]: expected value to equal [v8].
  log   [11:21:36.626] [warning][ui-settings-service] Ignore invalid UiSettings value. Error: [validation [theme:version]]: types that failed validation:
- [validation [theme:version].0]: expected value to equal [v7]
- [validation [theme:version].1]: expected value to equal [v8].
  log   [11:21:46.629] [warning][ui-settings-service] Ignore invalid UiSettings value. Error: [validation [theme:version]]: types that failed validation:
- [validation [theme:version].0]: expected value to equal [v7]
- [validation [theme:version].1]: expected value to equal [v8].
  log   [11:21:56.632] [warning][ui-settings-service] Ignore invalid UiSettings value. Error: [validation [theme:version]]: types that failed validation:
- [validation [theme:version].0]: expected value to equal [v7]
- [validation [theme:version].1]: expected value to equal [v8].
  log   [11:22:06.634] [warning][ui-settings-service] Ignore invalid UiSettings value. Error: [validation [theme:version]]: types that failed validation:
- [validation [theme:version].0]: expected value to equal [v7]
- [validation [theme:version].1]: expected value to equal [v8].
  log   [11:22:16.637] [warning][ui-settings-service] Ignore invalid UiSettings value. Error: [validation [theme:version]]: types that failed validation:
- [validation [theme:version].0]: expected value to equal [v7]
- [validation [theme:version].1]: expected value to equal [v8].

I don't know when they started, I only noticed them when I launched kibana interactively to test some timeout changes.

I don't have any theme settings in my kibana.yml, and if I use the Kibana dashboards Stack Management:Advanced Settings page and filter for the word 'theme' I see that hte 'dark mode' toggle is 'on' and the "theme:version: dropdown is set to 'v8' (and the only options in that dropdown are v7 and v8).

The only thing I could think of was to change those two settings (light & v7), saved, let it refresh for awhile, then set them back (dark & v8).

That seems to have done the trick and the log spew stopped - but perhaps a more actionable message or some 'self-healing' in the code would be better.

Hi there,
thank you so much for raising it. I went through our open issues and couldn't find anything related to it, but I'll keep an eye on it. If the problem occurs again, please reach out.