When an object has an operator function and a code from other project uses the operator function the import of the object is marked as unused.

This results CVS commits with remove unused imports option active to actually break the code.

Test.kt

package pkg

object Test {
    operator fun plusAssign(a: Int) {
        println("a: $a")
    }
}

main.kt

import pkg.Test

fun main() {
    Test += 12
}