diff --git a/CHANGELOG.md b/CHANGELOG.md
index 96018c669..f965bcb23 100644
--- a/CHANGELOG.md
+++ b/CHANGELOG.md
@@ -33,6 +33,7 @@ All notable changes to this project will be documented in this file.
 - AS3 - getouterscope instruction support
 - [#1990] Cloning DefineSprite causing incorrect tags written
 - Do not display fonts added to stage (for example in testdata/as2.swf, the vertical text - sprite 10)
+- AS2 Class detection - TemporaryRegisterMark handling
 
 ### Changed
 - AS1/2/3 P-code - format Number values with EcmaScript toString function
diff --git a/libsrc/ffdec_lib/src/com/jpexs/decompiler/flash/action/ActionScript2ClassDetector.java b/libsrc/ffdec_lib/src/com/jpexs/decompiler/flash/action/ActionScript2ClassDetector.java
index d97985409..32abd2ec7 100644
--- a/libsrc/ffdec_lib/src/com/jpexs/decompiler/flash/action/ActionScript2ClassDetector.java
+++ b/libsrc/ffdec_lib/src/com/jpexs/decompiler/flash/action/ActionScript2ClassDetector.java
@@ -32,6 +32,7 @@ import com.jpexs.decompiler.flash.action.model.SetMemberActionItem;
 import com.jpexs.decompiler.flash.action.model.SetVariableActionItem;
 import com.jpexs.decompiler.flash.action.model.StoreRegisterActionItem;
 import com.jpexs.decompiler.flash.action.model.TemporaryRegister;
+import com.jpexs.decompiler.flash.action.model.TemporaryRegisterMark;
 import com.jpexs.decompiler.flash.action.model.clauses.ClassActionItem;
 import com.jpexs.decompiler.flash.action.model.clauses.InterfaceActionItem;
 import com.jpexs.decompiler.flash.action.swf4.RegisterNumber;
@@ -699,6 +700,8 @@ public class ActionScript2ClassDetector {
                     //TODO: maybe somehow display in the class ?
                 } else if (item instanceof ScriptEndItem) {
                     //ignore
+                } else if (item instanceof TemporaryRegisterMark) {
+                    //ignore
                 } else {
                     throw new AssertException("unknown item - " + item.getClass().getSimpleName());
                 }