Filter using calculated field in dropdown control triggers system error(Error ID: dac9ad63)

[Jack0723]

Hi Looker Studio Team,

I encountered a system error when using a calculated field as a filter in a dropdown list control.

Here’s what I did:
- I created a Calculated Property using a CASE expression to categorize Full page URL values.
- The values display correctly in the dropdown list control.
- However, when I select any option from the dropdown, the page or panel throws a system error:

System error
Looker Studio has encountered a system error.
Error ID: dac9ad63

What I have tried:
- Made sure the CASE result types are consistent (all strings).
- Tried using ELSE Page title and also ELSE CONCAT("", Page title).
- Simplified the CASE to only a few rules — still causes the error.
- Tried removing the ELSE clause — still failed.

This seems like a bug related to using calculated fields as filters.

Could you please help check if this is a known issue or provide any workaround?

Thanks!