diff --git a/compiler/fir/analysis-tests/testData/resolveWithStdlib/callableReferences/ifWithCR.kt b/compiler/fir/analysis-tests/testData/resolveWithStdlib/callableReferences/ifWithCR.kt
index 1eacfbff8c8..6c6be29bea8 100644
--- a/compiler/fir/analysis-tests/testData/resolveWithStdlib/callableReferences/ifWithCR.kt
+++ b/compiler/fir/analysis-tests/testData/resolveWithStdlib/callableReferences/ifWithCR.kt
@@ -1,5 +1,5 @@
-<!MUST_BE_INITIALIZED!>private var Int.readOnlyWrapper: CharSequence?<!> get() = null
-<!MUST_BE_INITIALIZED!>private var Int.mutableWrapper: CharSequence?<!> get() = null
+<!EXTENSION_PROPERTY_MUST_HAVE_ACCESSORS_OR_BE_ABSTRACT!>private var Int.readOnlyWrapper: CharSequence?<!> get() = null
+<!EXTENSION_PROPERTY_MUST_HAVE_ACCESSORS_OR_BE_ABSTRACT!>private var Int.mutableWrapper: CharSequence?<!> get() = null
 
 fun main(x: Int) {
     val x = if (x > 1) x::readOnlyWrapper else x::mutableWrapper
diff --git a/compiler/fir/checkers/src/org/jetbrains/kotlin/fir/analysis/checkers/declaration/FirTopLevelPropertiesChecker.kt b/compiler/fir/checkers/src/org/jetbrains/kotlin/fir/analysis/checkers/declaration/FirTopLevelPropertiesChecker.kt
index 6523fa6a080..08b375c74c9 100644
--- a/compiler/fir/checkers/src/org/jetbrains/kotlin/fir/analysis/checkers/declaration/FirTopLevelPropertiesChecker.kt
+++ b/compiler/fir/checkers/src/org/jetbrains/kotlin/fir/analysis/checkers/declaration/FirTopLevelPropertiesChecker.kt
@@ -130,7 +130,7 @@ internal fun checkPropertyInitializer(
                 !isExternal &&
                 !property.hasExplicitBackingField
             ) {
-                if (property.receiverParameter != null && !property.hasAnyAccessorImplementation) {
+                if (property.receiverParameter != null && !property.hasAllAccessorImplementation) {
                     reporter.reportOn(propertySource, FirErrors.EXTENSION_PROPERTY_MUST_HAVE_ACCESSORS_OR_BE_ABSTRACT, context)
                 } else if (reachable) {
                     reportMustBeInitialized(property, isDefinitelyAssignedInConstructor, containingClass, propertySource, reporter, context)
@@ -209,6 +209,9 @@ private val FirProperty.hasSetterAccessorImplementation: Boolean
 private val FirProperty.hasAnyAccessorImplementation: Boolean
     get() = getter.hasImplementation || setter.hasImplementation
 
+private val FirProperty.hasAllAccessorImplementation: Boolean
+    get() = getter.hasImplementation && (isVal || setter.hasImplementation)
+
 private fun FirProperty.getEffectiveModality(containingClass: FirClass?, languageVersionSettings: LanguageVersionSettings): Modality? =
     when (languageVersionSettings.supportsFeature(LanguageFeature.TakeIntoAccountEffectivelyFinalInMustBeInitializedCheck) &&
             status.modality == Modality.OPEN && containingClass?.status?.modality == Modality.FINAL) {
diff --git a/compiler/tests/org/jetbrains/kotlin/jvm/compiler/AbstractCompileKotlinAgainstCustomBinariesTest.kt b/compiler/tests/org/jetbrains/kotlin/jvm/compiler/AbstractCompileKotlinAgainstCustomBinariesTest.kt
index 9d46fe661c2..db57994f89d 100644
--- a/compiler/tests/org/jetbrains/kotlin/jvm/compiler/AbstractCompileKotlinAgainstCustomBinariesTest.kt
+++ b/compiler/tests/org/jetbrains/kotlin/jvm/compiler/AbstractCompileKotlinAgainstCustomBinariesTest.kt
@@ -663,8 +663,7 @@ abstract class AbstractCompileKotlinAgainstCustomBinariesTest : AbstractKotlinCo
         compileKotlin("main.kt", tmpdir, listOf(library), additionalOptions = features)
     }
 
-    // Fixed in the LV2.0 branch.
-    fun testUnreachableExtensionVarPropertyDeclaration() = muteForK2 {
+    fun testUnreachableExtensionVarPropertyDeclaration() {
         val (output, exitCode) = compileKotlin("source.kt", tmpdir, expectedFileName = null)
         assertEquals("Output:\n$output", ExitCode.COMPILATION_ERROR, exitCode)
     }