diff --git a/compiler/testData/codegen/box/closures/captureInSuperConstructorCall/outerCapturedInPrimaryConstructorDefaultParameter.kt b/compiler/testData/codegen/box/closures/captureInSuperConstructorCall/outerCapturedInPrimaryConstructorDefaultParameter.kt
index 54a0d0f1f01..33d76ea670d 100644
--- a/compiler/testData/codegen/box/closures/captureInSuperConstructorCall/outerCapturedInPrimaryConstructorDefaultParameter.kt
+++ b/compiler/testData/codegen/box/closures/captureInSuperConstructorCall/outerCapturedInPrimaryConstructorDefaultParameter.kt
@@ -1,4 +1,5 @@
 // IGNORE_BACKEND_K2: JS_IR, JS_IR_ES6, WASM
+// K2 issue: KT-64801
 
 class Outer(val x: Any) {
     inner class Inner(
@@ -6,4 +7,4 @@ class Outer(val x: Any) {
     )
 }
 
-fun box() = Outer("OK").Inner().fn()
\ No newline at end of file
+fun box() = Outer("OK").Inner().fn()
diff --git a/compiler/testData/codegen/box/closures/captureInSuperConstructorCall/outerCapturedInSecondaryConstructorDefaultParameter.kt b/compiler/testData/codegen/box/closures/captureInSuperConstructorCall/outerCapturedInSecondaryConstructorDefaultParameter.kt
index c0bc719c792..e2c0de2c53c 100644
--- a/compiler/testData/codegen/box/closures/captureInSuperConstructorCall/outerCapturedInSecondaryConstructorDefaultParameter.kt
+++ b/compiler/testData/codegen/box/closures/captureInSuperConstructorCall/outerCapturedInSecondaryConstructorDefaultParameter.kt
@@ -1,4 +1,5 @@
 // IGNORE_BACKEND_K2: JS_IR, JS_IR_ES6, WASM
+// K2 issue: KT-64801
 
 class Outer(val x: Any) {
     inner class Inner(
@@ -11,4 +12,4 @@ class Outer(val x: Any) {
     }
 }
 
-fun box() = Outer("OK").Inner(1).fn()
\ No newline at end of file
+fun box() = Outer("OK").Inner(1).fn()
diff --git a/compiler/testData/codegen/box/delegatedProperty/delegateToAnother/genericJavaProperty.kt b/compiler/testData/codegen/box/delegatedProperty/delegateToAnother/genericJavaProperty.kt
index 3b68569c36e..680c44935e7 100644
--- a/compiler/testData/codegen/box/delegatedProperty/delegateToAnother/genericJavaProperty.kt
+++ b/compiler/testData/codegen/box/delegatedProperty/delegateToAnother/genericJavaProperty.kt
@@ -1,5 +1,4 @@
 // TARGET_BACKEND: JVM
-// IGNORE_BACKEND_K2: JS_IR, JS_IR_ES6
 // WITH_REFLECT
 // WITH_STDLIB
 // FILE: J.java
diff --git a/compiler/testData/codegen/box/extensionClasses/constructors.kt b/compiler/testData/codegen/box/extensionClasses/constructors.kt
index 1daab3bc8ac..dbfd4f96d59 100644
--- a/compiler/testData/codegen/box/extensionClasses/constructors.kt
+++ b/compiler/testData/codegen/box/extensionClasses/constructors.kt
@@ -1,6 +1,5 @@
 // !LANGUAGE: +ContextReceivers
 // TARGET_BACKEND: JVM_IR
-// IGNORE_BACKEND_K2: JS_IR, JS_IR_ES6
 // WITH_STDLIB
 
 class A(val ok: String)
diff --git a/compiler/testData/codegen/box/innerNested/innerWithDefaultInner.kt b/compiler/testData/codegen/box/innerNested/innerWithDefaultInner.kt
index 58c5e8cd6f9..6c4e7e514c8 100644
--- a/compiler/testData/codegen/box/innerNested/innerWithDefaultInner.kt
+++ b/compiler/testData/codegen/box/innerNested/innerWithDefaultInner.kt
@@ -1,5 +1,5 @@
 // IGNORE_BACKEND_K2: JS_IR, JS_IR_ES6, WASM
-
+// K2 issue: KT-64801
 // KT-40686
 
 
@@ -22,4 +22,4 @@ fun box(): String {
     if (rr != "ABC") return "FAIL: $rr"
 
     return "OK"
-}
\ No newline at end of file
+}
diff --git a/compiler/testData/codegen/box/multiplatform/expectClassInJvmMultifileFacade.kt b/compiler/testData/codegen/box/multiplatform/expectClassInJvmMultifileFacade.kt
index cbb883878cb..a22a1b87e9e 100644
--- a/compiler/testData/codegen/box/multiplatform/expectClassInJvmMultifileFacade.kt
+++ b/compiler/testData/codegen/box/multiplatform/expectClassInJvmMultifileFacade.kt
@@ -1,5 +1,4 @@
 // !LANGUAGE: +MultiPlatformProjects
-// IGNORE_BACKEND_K2: JVM_IR, JS_IR
 // FIR status: expect/actual in the same module (ACTUAL_WITHOUT_EXPECT)
 // TARGET_BACKEND: JVM
 // IGNORE_BACKEND_K2: ANY
diff --git a/compiler/testData/codegen/box/when/enumOptimization/kt14802.kt b/compiler/testData/codegen/box/when/enumOptimization/kt14802.kt
index 4d34d166d30..28b3245563a 100644
--- a/compiler/testData/codegen/box/when/enumOptimization/kt14802.kt
+++ b/compiler/testData/codegen/box/when/enumOptimization/kt14802.kt
@@ -1,8 +1,5 @@
-// IGNORE_BACKEND_K2: JS_IR, JS_IR_ES6
 // CHECK_CASES_COUNT: function=crash count=2 TARGET_BACKENDS=JS
-// CHECK_CASES_COUNT: function=crash count=0 IGNORED_BACKENDS=JS
 // CHECK_IF_COUNT: function=crash count=1 TARGET_BACKENDS=JS
-// CHECK_IF_COUNT: function=crash count=3 IGNORED_BACKENDS=JS
 
 class EncapsulatedEnum<T : Enum<T>>(val value: T)
 
@@ -28,4 +25,4 @@ var res = "fail"
 fun box(): String {
     crash(EncapsulatedEnum(MyEnum.VALUE_A))
     return res
-}
\ No newline at end of file
+}
diff --git a/compiler/testData/codegen/box/when/enumOptimization/kt15806.kt b/compiler/testData/codegen/box/when/enumOptimization/kt15806.kt
index 71d00ee1d91..9c6a3e160b5 100644
--- a/compiler/testData/codegen/box/when/enumOptimization/kt15806.kt
+++ b/compiler/testData/codegen/box/when/enumOptimization/kt15806.kt
@@ -1,9 +1,6 @@
-// IGNORE_BACKEND_K2: JS_IR, JS_IR_ES6
 // JVM_ABI_K1_K2_DIFF: KT-62903
 // CHECK_CASES_COUNT: function=doTheThing count=2 TARGET_BACKENDS=JS
-// CHECK_CASES_COUNT: function=doTheThing count=0 IGNORED_BACKENDS=JS
 // CHECK_IF_COUNT: function=doTheThing count=2 TARGET_BACKENDS=JS
-// CHECK_IF_COUNT: function=doTheThing count=4 IGNORED_BACKENDS=JS
 
 private fun Any?.doTheThing(): String {
     when (this) {
@@ -28,4 +25,4 @@ enum class Level {
 
 fun box(): String {
     return "O".doTheThing() + Level.K.doTheThing()
-}
\ No newline at end of file
+}
diff --git a/compiler/testData/codegen/boxError/semantic/mismatchTypeParameters.kt b/compiler/testData/codegen/boxError/semantic/mismatchTypeParameters.kt
index 1aac52e2da4..4f08353b41e 100644
--- a/compiler/testData/codegen/boxError/semantic/mismatchTypeParameters.kt
+++ b/compiler/testData/codegen/boxError/semantic/mismatchTypeParameters.kt
@@ -1,6 +1,7 @@
 // IGNORE_ERRORS
 // ERROR_POLICY: SEMANTIC
 // IGNORE_BACKEND_K2: JS_IR, JS_IR_ES6
+// K2 issue: KT-55250
 
 // MODULE: lib
 // FILE: t.kt
@@ -20,4 +21,4 @@ fun foo() {
 fun box(): String {
     foo()
     return storage
-}
\ No newline at end of file
+}
diff --git a/compiler/testData/codegen/boxError/semantic/typeMismatch.kt b/compiler/testData/codegen/boxError/semantic/typeMismatch.kt
index 8a9618c755e..1d5b2c31d63 100644
--- a/compiler/testData/codegen/boxError/semantic/typeMismatch.kt
+++ b/compiler/testData/codegen/boxError/semantic/typeMismatch.kt
@@ -1,6 +1,7 @@
 // IGNORE_ERRORS
 // ERROR_POLICY: SEMANTIC
 // IGNORE_BACKEND_K2: JS_IR, JS_IR_ES6
+// K2 issue: KT-64810
 
 // MODULE: lib
 // FILE: t.kt
@@ -23,4 +24,4 @@ fun box(): String {
         return "OK"
     }
     return "FAIL"
-}
\ No newline at end of file
+}
diff --git a/compiler/testData/codegen/boxError/semantic/unmatchedArguments.kt b/compiler/testData/codegen/boxError/semantic/unmatchedArguments.kt
index 7de65693333..7ae2474e104 100644
--- a/compiler/testData/codegen/boxError/semantic/unmatchedArguments.kt
+++ b/compiler/testData/codegen/boxError/semantic/unmatchedArguments.kt
@@ -1,6 +1,7 @@
 // IGNORE_ERRORS
 // ERROR_POLICY: SEMANTIC
 // IGNORE_BACKEND_K2: JS_IR, JS_IR_ES6
+// K2 issue: KT-64817
 
 // MODULE: lib
 // FILE: t.kt
@@ -32,4 +33,4 @@ fun box(): String {
         }
     }
     return "FAIL"
-}
\ No newline at end of file
+}
diff --git a/compiler/testData/codegen/boxError/syntax/incorectLexicalName.kt b/compiler/testData/codegen/boxError/syntax/incorectLexicalName.kt
index b4370cf9793..b41e23a5ab7 100644
--- a/compiler/testData/codegen/boxError/syntax/incorectLexicalName.kt
+++ b/compiler/testData/codegen/boxError/syntax/incorectLexicalName.kt
@@ -1,6 +1,7 @@
 // IGNORE_ERRORS
 // ERROR_POLICY: SYNTAX
 // IGNORE_BACKEND_K2: JS_IR, JS_IR_ES6
+// K2 issue: KT-64845
 
 // MODULE: lib
 // FILE: t.kt
@@ -39,4 +40,4 @@ fun box(): String {
         }
     }
     return "FAIL"
-}
\ No newline at end of file
+}
diff --git a/compiler/testData/codegen/boxError/syntax/missedArgument.kt b/compiler/testData/codegen/boxError/syntax/missedArgument.kt
index f805ebe1389..4c46feb87c3 100644
--- a/compiler/testData/codegen/boxError/syntax/missedArgument.kt
+++ b/compiler/testData/codegen/boxError/syntax/missedArgument.kt
@@ -1,6 +1,7 @@
 // IGNORE_ERRORS
 // ERROR_POLICY: SYNTAX
 // IGNORE_BACKEND_K2: JS_IR, JS_IR_ES6
+// K2 issue: KT-64820
 
 // MODULE: lib
 // FILE: t.kt
@@ -21,4 +22,4 @@ fun box(): String {
         return "OK"
     }
     return "FAIL"
-}
\ No newline at end of file
+}
diff --git a/compiler/testData/ir/irText/js/dynamic/dynamicArrayIncrementDecrement.fir.ir.txt b/compiler/testData/ir/irText/js/dynamic/dynamicArrayIncrementDecrement.fir.ir.txt
new file mode 100644
index 00000000000..68417b0b7fd
--- /dev/null
+++ b/compiler/testData/ir/irText/js/dynamic/dynamicArrayIncrementDecrement.fir.ir.txt
@@ -0,0 +1,52 @@
+FILE fqName:<root> fileName:/dynamicArrayIncrementDecrement.kt
+  FUN name:testArrayIncrementDecrement visibility:public modality:FINAL <> (d:dynamic) returnType:kotlin.Unit
+    VALUE_PARAMETER name:d index:0 type:dynamic
+    BLOCK_BODY
+      VAR name:t1 type:dynamic [val]
+        BLOCK type=dynamic origin=null
+          VAR IR_TEMPORARY_VARIABLE name:tmp_0 type:dynamic [val]
+            GET_VAR 'd: dynamic declared in <root>.testArrayIncrementDecrement' type=dynamic origin=null
+          VAR IR_TEMPORARY_VARIABLE name:tmp_1 type:kotlin.String [val]
+            CONST String type=kotlin.String value="prefixIncr"
+          TYPE_OP type=kotlin.Unit origin=IMPLICIT_COERCION_TO_UNIT typeOperand=kotlin.Unit
+            DYN_OP operator=INVOKE type=dynamic
+              receiver: DYN_MEMBER memberName='set' type=dynamic
+                GET_VAR 'val tmp_0: dynamic declared in <root>.testArrayIncrementDecrement' type=dynamic origin=null
+              0: GET_VAR 'val tmp_1: kotlin.String declared in <root>.testArrayIncrementDecrement' type=kotlin.String origin=null
+              1: DYN_OP operator=PREFIX_INCREMENT type=dynamic
+                receiver: DYN_OP operator=ARRAY_ACCESS type=dynamic
+                  receiver: GET_VAR 'val tmp_0: dynamic declared in <root>.testArrayIncrementDecrement' type=dynamic origin=null
+                  0: GET_VAR 'val tmp_1: kotlin.String declared in <root>.testArrayIncrementDecrement' type=kotlin.String origin=null
+          DYN_OP operator=INVOKE type=dynamic
+            receiver: DYN_MEMBER memberName='get' type=dynamic
+              GET_VAR 'val tmp_0: dynamic declared in <root>.testArrayIncrementDecrement' type=dynamic origin=null
+            0: GET_VAR 'val tmp_1: kotlin.String declared in <root>.testArrayIncrementDecrement' type=kotlin.String origin=null
+      VAR name:t2 type:dynamic [val]
+        BLOCK type=dynamic origin=null
+          VAR IR_TEMPORARY_VARIABLE name:tmp_2 type:dynamic [val]
+            GET_VAR 'd: dynamic declared in <root>.testArrayIncrementDecrement' type=dynamic origin=null
+          VAR IR_TEMPORARY_VARIABLE name:tmp_3 type:kotlin.String [val]
+            CONST String type=kotlin.String value="prefixDecr"
+          TYPE_OP type=kotlin.Unit origin=IMPLICIT_COERCION_TO_UNIT typeOperand=kotlin.Unit
+            DYN_OP operator=INVOKE type=dynamic
+              receiver: DYN_MEMBER memberName='set' type=dynamic
+                GET_VAR 'val tmp_2: dynamic declared in <root>.testArrayIncrementDecrement' type=dynamic origin=null
+              0: GET_VAR 'val tmp_3: kotlin.String declared in <root>.testArrayIncrementDecrement' type=kotlin.String origin=null
+              1: DYN_OP operator=PREFIX_DECREMENT type=dynamic
+                receiver: DYN_OP operator=ARRAY_ACCESS type=dynamic
+                  receiver: GET_VAR 'val tmp_2: dynamic declared in <root>.testArrayIncrementDecrement' type=dynamic origin=null
+                  0: GET_VAR 'val tmp_3: kotlin.String declared in <root>.testArrayIncrementDecrement' type=kotlin.String origin=null
+          DYN_OP operator=INVOKE type=dynamic
+            receiver: DYN_MEMBER memberName='get' type=dynamic
+              GET_VAR 'val tmp_2: dynamic declared in <root>.testArrayIncrementDecrement' type=dynamic origin=null
+            0: GET_VAR 'val tmp_3: kotlin.String declared in <root>.testArrayIncrementDecrement' type=kotlin.String origin=null
+      VAR name:t3 type:dynamic [val]
+        DYN_OP operator=POSTFIX_INCREMENT type=dynamic
+          receiver: DYN_OP operator=ARRAY_ACCESS type=dynamic
+            receiver: GET_VAR 'd: dynamic declared in <root>.testArrayIncrementDecrement' type=dynamic origin=null
+            0: CONST String type=kotlin.String value="postfixIncr"
+      VAR name:t4 type:dynamic [val]
+        DYN_OP operator=POSTFIX_DECREMENT type=dynamic
+          receiver: DYN_OP operator=ARRAY_ACCESS type=dynamic
+            receiver: GET_VAR 'd: dynamic declared in <root>.testArrayIncrementDecrement' type=dynamic origin=null
+            0: CONST String type=kotlin.String value="postfixDecr"
diff --git a/compiler/testData/ir/irText/js/dynamic/dynamicArrayIncrementDecrement.fir.kt.txt b/compiler/testData/ir/irText/js/dynamic/dynamicArrayIncrementDecrement.fir.kt.txt
new file mode 100644
index 00000000000..0bb070e81c4
--- /dev/null
+++ b/compiler/testData/ir/irText/js/dynamic/dynamicArrayIncrementDecrement.fir.kt.txt
@@ -0,0 +1,16 @@
+fun testArrayIncrementDecrement(d: dynamic) {
+  val t1: dynamic = { // BLOCK
+    val tmp_0: dynamic = d
+    val tmp_1: String = "prefixIncr"
+    tmp_0.set(tmp_1, ++tmp_0[tmp_1]) /*~> Unit */
+    tmp_0.get(tmp_1)
+  }
+  val t2: dynamic = { // BLOCK
+    val tmp_2: dynamic = d
+    val tmp_3: String = "prefixDecr"
+    tmp_2.set(tmp_3, --tmp_2[tmp_3]) /*~> Unit */
+    tmp_2.get(tmp_3)
+  }
+  val t3: dynamic = d["postfixIncr"]++
+  val t4: dynamic = d["postfixDecr"]--
+}
diff --git a/compiler/testData/ir/irText/js/dynamic/dynamicArrayIncrementDecrement.kt b/compiler/testData/ir/irText/js/dynamic/dynamicArrayIncrementDecrement.kt
index 028727bb4e1..e393a66ebd8 100644
--- a/compiler/testData/ir/irText/js/dynamic/dynamicArrayIncrementDecrement.kt
+++ b/compiler/testData/ir/irText/js/dynamic/dynamicArrayIncrementDecrement.kt
@@ -1,7 +1,4 @@
 // TARGET_BACKEND: JS_IR
-// FIR_IDENTICAL
-
-// IGNORE_BACKEND_K2: JS_IR
 
 fun testArrayIncrementDecrement(d: dynamic) {
     val t1 = ++d["prefixIncr"]
diff --git a/compiler/testData/ir/irText/js/dynamic/dynamicMemberIncrementDecrement.fir.ir.txt b/compiler/testData/ir/irText/js/dynamic/dynamicMemberIncrementDecrement.fir.ir.txt
new file mode 100644
index 00000000000..98bc92b4314
--- /dev/null
+++ b/compiler/testData/ir/irText/js/dynamic/dynamicMemberIncrementDecrement.fir.ir.txt
@@ -0,0 +1,97 @@
+FILE fqName:<root> fileName:/dynamicMemberIncrementDecrement.kt
+  FUN name:testMemberIncrementDecrement visibility:public modality:FINAL <> (d:dynamic) returnType:kotlin.Unit
+    VALUE_PARAMETER name:d index:0 type:dynamic
+    BLOCK_BODY
+      VAR name:t1 type:dynamic [val]
+        DYN_OP operator=PREFIX_INCREMENT type=dynamic
+          receiver: GET_VAR 'd: dynamic declared in <root>.testMemberIncrementDecrement' type=dynamic origin=null
+      VAR name:t2 type:dynamic [val]
+        DYN_OP operator=PREFIX_DECREMENT type=dynamic
+          receiver: GET_VAR 'd: dynamic declared in <root>.testMemberIncrementDecrement' type=dynamic origin=null
+      VAR name:t3 type:dynamic [val]
+        DYN_OP operator=POSTFIX_INCREMENT type=dynamic
+          receiver: DYN_MEMBER memberName='postfixIncr' type=dynamic
+            GET_VAR 'd: dynamic declared in <root>.testMemberIncrementDecrement' type=dynamic origin=null
+      VAR name:t4 type:dynamic [val]
+        DYN_OP operator=POSTFIX_DECREMENT type=dynamic
+          receiver: DYN_MEMBER memberName='postfixDecr' type=dynamic
+            GET_VAR 'd: dynamic declared in <root>.testMemberIncrementDecrement' type=dynamic origin=null
+  FUN name:testSafeMemberIncrementDecrement visibility:public modality:FINAL <> (d:dynamic) returnType:kotlin.Unit
+    VALUE_PARAMETER name:d index:0 type:dynamic
+    BLOCK_BODY
+      VAR name:t1 type:dynamic [val]
+        BLOCK type=dynamic origin=SAFE_CALL
+          VAR IR_TEMPORARY_VARIABLE name:tmp_0 type:dynamic [val]
+            GET_VAR 'd: dynamic declared in <root>.testSafeMemberIncrementDecrement' type=dynamic origin=null
+          WHEN type=dynamic origin=null
+            BRANCH
+              if: CALL 'public final fun EQEQ (arg0: kotlin.Any?, arg1: kotlin.Any?): kotlin.Boolean declared in kotlin.internal.ir' type=kotlin.Boolean origin=EQEQ
+                arg0: GET_VAR 'val tmp_0: dynamic declared in <root>.testSafeMemberIncrementDecrement' type=dynamic origin=null
+                arg1: CONST Null type=kotlin.Nothing? value=null
+              then: CONST Null type=kotlin.Nothing? value=null
+            BRANCH
+              if: CONST Boolean type=kotlin.Boolean value=true
+              then: BLOCK type=dynamic origin=null
+                VAR IR_TEMPORARY_VARIABLE name:tmp_1 type:dynamic [val]
+                  GET_VAR 'val tmp_0: dynamic declared in <root>.testSafeMemberIncrementDecrement' type=dynamic origin=null
+                DYN_OP operator=EQ type=kotlin.Unit
+                  receiver: DYN_MEMBER memberName='prefixIncr' type=kotlin.Unit
+                    GET_VAR 'val tmp_1: dynamic declared in <root>.testSafeMemberIncrementDecrement' type=dynamic origin=null
+                  0: DYN_OP operator=PREFIX_INCREMENT type=dynamic
+                    receiver: DYN_MEMBER memberName='prefixIncr' type=dynamic
+                      GET_VAR 'val tmp_1: dynamic declared in <root>.testSafeMemberIncrementDecrement' type=dynamic origin=null
+                DYN_MEMBER memberName='prefixIncr' type=dynamic
+                  GET_VAR 'val tmp_1: dynamic declared in <root>.testSafeMemberIncrementDecrement' type=dynamic origin=null
+      VAR name:t2 type:dynamic [val]
+        BLOCK type=dynamic origin=SAFE_CALL
+          VAR IR_TEMPORARY_VARIABLE name:tmp_2 type:dynamic [val]
+            GET_VAR 'd: dynamic declared in <root>.testSafeMemberIncrementDecrement' type=dynamic origin=null
+          WHEN type=dynamic origin=null
+            BRANCH
+              if: CALL 'public final fun EQEQ (arg0: kotlin.Any?, arg1: kotlin.Any?): kotlin.Boolean declared in kotlin.internal.ir' type=kotlin.Boolean origin=EQEQ
+                arg0: GET_VAR 'val tmp_2: dynamic declared in <root>.testSafeMemberIncrementDecrement' type=dynamic origin=null
+                arg1: CONST Null type=kotlin.Nothing? value=null
+              then: CONST Null type=kotlin.Nothing? value=null
+            BRANCH
+              if: CONST Boolean type=kotlin.Boolean value=true
+              then: BLOCK type=dynamic origin=null
+                VAR IR_TEMPORARY_VARIABLE name:tmp_3 type:dynamic [val]
+                  GET_VAR 'val tmp_2: dynamic declared in <root>.testSafeMemberIncrementDecrement' type=dynamic origin=null
+                DYN_OP operator=EQ type=kotlin.Unit
+                  receiver: DYN_MEMBER memberName='prefixDecr' type=kotlin.Unit
+                    GET_VAR 'val tmp_3: dynamic declared in <root>.testSafeMemberIncrementDecrement' type=dynamic origin=null
+                  0: DYN_OP operator=PREFIX_DECREMENT type=dynamic
+                    receiver: DYN_MEMBER memberName='prefixDecr' type=dynamic
+                      GET_VAR 'val tmp_3: dynamic declared in <root>.testSafeMemberIncrementDecrement' type=dynamic origin=null
+                DYN_MEMBER memberName='prefixDecr' type=dynamic
+                  GET_VAR 'val tmp_3: dynamic declared in <root>.testSafeMemberIncrementDecrement' type=dynamic origin=null
+      VAR name:t3 type:dynamic [val]
+        BLOCK type=dynamic origin=SAFE_CALL
+          VAR IR_TEMPORARY_VARIABLE name:tmp_4 type:dynamic [val]
+            GET_VAR 'd: dynamic declared in <root>.testSafeMemberIncrementDecrement' type=dynamic origin=null
+          WHEN type=dynamic origin=null
+            BRANCH
+              if: CALL 'public final fun EQEQ (arg0: kotlin.Any?, arg1: kotlin.Any?): kotlin.Boolean declared in kotlin.internal.ir' type=kotlin.Boolean origin=EQEQ
+                arg0: GET_VAR 'val tmp_4: dynamic declared in <root>.testSafeMemberIncrementDecrement' type=dynamic origin=null
+                arg1: CONST Null type=kotlin.Nothing? value=null
+              then: CONST Null type=kotlin.Nothing? value=null
+            BRANCH
+              if: CONST Boolean type=kotlin.Boolean value=true
+              then: DYN_OP operator=POSTFIX_INCREMENT type=dynamic
+                receiver: DYN_MEMBER memberName='postfixIncr' type=dynamic
+                  GET_VAR 'val tmp_4: dynamic declared in <root>.testSafeMemberIncrementDecrement' type=dynamic origin=null
+      VAR name:t4 type:dynamic [val]
+        BLOCK type=dynamic origin=SAFE_CALL
+          VAR IR_TEMPORARY_VARIABLE name:tmp_5 type:dynamic [val]
+            GET_VAR 'd: dynamic declared in <root>.testSafeMemberIncrementDecrement' type=dynamic origin=null
+          WHEN type=dynamic origin=null
+            BRANCH
+              if: CALL 'public final fun EQEQ (arg0: kotlin.Any?, arg1: kotlin.Any?): kotlin.Boolean declared in kotlin.internal.ir' type=kotlin.Boolean origin=EQEQ
+                arg0: GET_VAR 'val tmp_5: dynamic declared in <root>.testSafeMemberIncrementDecrement' type=dynamic origin=null
+                arg1: CONST Null type=kotlin.Nothing? value=null
+              then: CONST Null type=kotlin.Nothing? value=null
+            BRANCH
+              if: CONST Boolean type=kotlin.Boolean value=true
+              then: DYN_OP operator=POSTFIX_DECREMENT type=dynamic
+                receiver: DYN_MEMBER memberName='postfixDecr' type=dynamic
+                  GET_VAR 'val tmp_5: dynamic declared in <root>.testSafeMemberIncrementDecrement' type=dynamic origin=null
diff --git a/compiler/testData/ir/irText/js/dynamic/dynamicMemberIncrementDecrement.fir.kt.txt b/compiler/testData/ir/irText/js/dynamic/dynamicMemberIncrementDecrement.fir.kt.txt
new file mode 100644
index 00000000000..c3942e75ffd
--- /dev/null
+++ b/compiler/testData/ir/irText/js/dynamic/dynamicMemberIncrementDecrement.fir.kt.txt
@@ -0,0 +1,45 @@
+fun testMemberIncrementDecrement(d: dynamic) {
+  val t1: dynamic = ++d
+  val t2: dynamic = --d
+  val t3: dynamic = d.postfixIncr++
+  val t4: dynamic = d.postfixDecr--
+}
+
+fun testSafeMemberIncrementDecrement(d: dynamic) {
+  val t1: dynamic = { // BLOCK
+    val tmp_0: dynamic = d
+    when {
+      EQEQ(arg0 = tmp_0, arg1 = null) -> null
+      else -> { // BLOCK
+        val tmp_1: dynamic = tmp_0
+        tmp_1.prefixIncr = ++tmp_1.prefixIncr
+        tmp_1.prefixIncr
+      }
+    }
+  }
+  val t2: dynamic = { // BLOCK
+    val tmp_2: dynamic = d
+    when {
+      EQEQ(arg0 = tmp_2, arg1 = null) -> null
+      else -> { // BLOCK
+        val tmp_3: dynamic = tmp_2
+        tmp_3.prefixDecr = --tmp_3.prefixDecr
+        tmp_3.prefixDecr
+      }
+    }
+  }
+  val t3: dynamic = { // BLOCK
+    val tmp_4: dynamic = d
+    when {
+      EQEQ(arg0 = tmp_4, arg1 = null) -> null
+      else -> tmp_4.postfixIncr++
+    }
+  }
+  val t4: dynamic = { // BLOCK
+    val tmp_5: dynamic = d
+    when {
+      EQEQ(arg0 = tmp_5, arg1 = null) -> null
+      else -> tmp_5.postfixDecr--
+    }
+  }
+}
diff --git a/compiler/testData/ir/irText/js/dynamic/dynamicMemberIncrementDecrement.kt b/compiler/testData/ir/irText/js/dynamic/dynamicMemberIncrementDecrement.kt
index 09c4a3a2770..65ea7288537 100644
--- a/compiler/testData/ir/irText/js/dynamic/dynamicMemberIncrementDecrement.kt
+++ b/compiler/testData/ir/irText/js/dynamic/dynamicMemberIncrementDecrement.kt
@@ -1,7 +1,4 @@
 // TARGET_BACKEND: JS_IR
-// IGNORE_BACKEND_K2: JS_IR
-
-// FIR_IDENTICAL
 
 fun testMemberIncrementDecrement(d: dynamic) {
     val t1 = ++d.prefixIncr
diff --git a/js/js.translator/testData/box/export/vararg.kt b/js/js.translator/testData/box/export/vararg.kt
index 6e06606368b..3d55efbf003 100644
--- a/js/js.translator/testData/box/export/vararg.kt
+++ b/js/js.translator/testData/box/export/vararg.kt
@@ -1,9 +1,8 @@
-// IGNORE_BACKEND: JS
-// IGNORE_BACKEND_K2: JS_IR, JS_IR_ES6
 // EXPECTED_REACHABLE_NODES: 1270
 // SKIP_MINIFICATION
 // RUN_PLAIN_BOX_FUNCTION
 // INFER_MAIN_MODULE
+// WITH_STDLIB
 
 // MODULE: vararg
 // FILE: lib.kt
diff --git a/js/js.translator/testData/box/expression/when/exhaustiveCheckException.kt b/js/js.translator/testData/box/expression/when/exhaustiveCheckException.kt
index a671f923e3f..870f30c1a1d 100644
--- a/js/js.translator/testData/box/expression/when/exhaustiveCheckException.kt
+++ b/js/js.translator/testData/box/expression/when/exhaustiveCheckException.kt
@@ -1,4 +1,5 @@
 // IGNORE_BACKEND_K2: JS_IR, JS_IR_ES6
+// ISSUE: KT-64652
 // EXPECTED_REACHABLE_NODES: 1323
 fun <T> checkThrown(x: T, block: (T) -> Any?): Unit? {
     return try {
@@ -93,4 +94,4 @@ fun box(): String {
     } ?: return "fail8"
 
     return "OK"
-}
\ No newline at end of file
+}