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kotlinlang

Hi everyone, I have a 3-year old multiplatform project (jvm, js, ktor, react, redux components) that I'm having some difficulty trying to update to newer multiplatform versions. I tried to follow the commit history on the [jvm-js-fullstack](<https://github.com/kotlin-hands-on/jvm-js-fullstack/tree/final>) example to get to at least the 1.0.0-pre.561 version of the kotlin wrappers. That got my project to build, and the server side appears to work as intended, but the react and redux front end of it is failing in the browser.

My attempt at the update can be seen here: <https://github.com/hapifhir/org.hl7.fhir.validator-wrapper/compare/do-20251121-bump-kotlin-multiplatform>

The issues stem from redux from what I can tell. `The slice reducer for key "localizationSlice" returned undefined during initialization.` is what I can see in the browser console. I can get rid of that exception with some changes, but that leads to other runtime errors and I can't tell if it's actually an improvement.

If anyone has any ideas on the path I should take, or suggestions on more appropriate places to ask for help, please let me know.