I’m unable to find a 1.8.20-Beta (or 1.8.10) IDE plugin available in the EAP channel in IntelliJ 2023.1 EAP. Should I file an issue?

Seems like it only supports the next build

1.8.20 supports IDEA 2022.2 and 2022.3 - https://kotlinlang.org/docs/whatsnew-eap.html#ide-support

got it

This tripped me up as well. The What's New section titled "Preview of Gradle composite builds support in Kotlin Multiplatform" has a notice that "the feature is available since IntelliJ IDEA 2023.1 EAP 3 only", leading me to think I need to use 2023.1 EAP 3 with 1.8.20-Beta to make use of those changes. Since that's impossible to do, that section probably needs to be changed or removed.

Sorry for the inconvenience😔 You can use Latest IDEA 2023.1 + 1.8.20-Beta KGP, it works as expected