diff --git a/CHANGELOG.md b/CHANGELOG.md
index 241a4a226..a9e37e6d7 100644
--- a/CHANGELOG.md
+++ b/CHANGELOG.md
@@ -13,6 +13,7 @@ All notable changes to this project will be documented in this file.
 - AS3 XML embedded variables display and direct edit
 - AS3 Metadata values order
 - AS3 Metadata in P-code formatting
+- AS3 Metadata single value (null item key)
 
 ## [18.3.6] - 2023-02-25
 ### Fixed
diff --git a/libsrc/ffdec_lib/src/com/jpexs/decompiler/flash/abc/avm2/parser/pcode/ASM3Parser.java b/libsrc/ffdec_lib/src/com/jpexs/decompiler/flash/abc/avm2/parser/pcode/ASM3Parser.java
index 5ff2de100..ac36bd454 100644
--- a/libsrc/ffdec_lib/src/com/jpexs/decompiler/flash/abc/avm2/parser/pcode/ASM3Parser.java
+++ b/libsrc/ffdec_lib/src/com/jpexs/decompiler/flash/abc/avm2/parser/pcode/ASM3Parser.java
@@ -156,8 +156,10 @@ public class ASM3Parser {
                 Map<String, String> items = new HashMap<>();
                 while (symb.type == ParsedSymbol.TYPE_KEYWORD_ITEM) {
                     symb = lexer.lex();
-                    expected(symb, ParsedSymbol.TYPE_STRING, "string key");
-                    String key = (String) symb.value;
+                    if (symb.type != ParsedSymbol.TYPE_KEYWORD_NULL && symb.type != ParsedSymbol.TYPE_STRING) {
+                        throw new AVM2ParseException("string/null value expected", lexer.yyline());
+                    }
+                    String key = symb.type == ParsedSymbol.TYPE_KEYWORD_NULL ? null : (String) symb.value;
                     symb = lexer.lex();
                     expected(symb, ParsedSymbol.TYPE_STRING, "string value");
                     String val = (String) symb.value;
diff --git a/libsrc/ffdec_lib/src/com/jpexs/decompiler/flash/abc/types/traits/Trait.java b/libsrc/ffdec_lib/src/com/jpexs/decompiler/flash/abc/types/traits/Trait.java
index a93ef84b3..2044df86c 100644
--- a/libsrc/ffdec_lib/src/com/jpexs/decompiler/flash/abc/types/traits/Trait.java
+++ b/libsrc/ffdec_lib/src/com/jpexs/decompiler/flash/abc/types/traits/Trait.java
@@ -433,15 +433,23 @@ public abstract class Trait implements Cloneable, Serializable {
                         int val = abc.metadata_info.get(m).values[i];
                         writer.append("item ");
 
-                        writer.append("\"");
-                        writer.append(Helper.escapePCodeString(abc.constants.getString(key)));
-                        writer.append("\"");
+                        if (key == 0) {
+                            writer.append("null");
+                        } else {
+                            writer.append("\"");
+                            writer.append(Helper.escapePCodeString(abc.constants.getString(key)));
+                            writer.append("\"");
+                        }
 
                         writer.append(" ");
 
-                        writer.append("\"");
-                        writer.append(Helper.escapePCodeString(abc.constants.getString(val)));
-                        writer.append("\"");
+                        if (val == 0) {
+                            writer.append("null");
+                        } else {
+                            writer.append("\"");
+                            writer.append(Helper.escapePCodeString(abc.constants.getString(val)));
+                            writer.append("\"");
+                        }
                         writer.newLine();
                     }
                 }
diff --git a/libsrc/ffdec_lib/testdata/as3_new/bin/as3_new.air.swf b/libsrc/ffdec_lib/testdata/as3_new/bin/as3_new.air.swf
index 81b7eb9e4..256687182 100644
Binary files a/libsrc/ffdec_lib/testdata/as3_new/bin/as3_new.air.swf and b/libsrc/ffdec_lib/testdata/as3_new/bin/as3_new.air.swf differ
diff --git a/libsrc/ffdec_lib/testdata/as3_new/bin/as3_new.flex.swf b/libsrc/ffdec_lib/testdata/as3_new/bin/as3_new.flex.swf
index 703048be5..4843abd9b 100644
Binary files a/libsrc/ffdec_lib/testdata/as3_new/bin/as3_new.flex.swf and b/libsrc/ffdec_lib/testdata/as3_new/bin/as3_new.flex.swf differ
diff --git a/libsrc/ffdec_lib/testdata/as3_new/src/tests/TestMetadata.as b/libsrc/ffdec_lib/testdata/as3_new/src/tests/TestMetadata.as
index 6d28ce979..9c4b34824 100644
--- a/libsrc/ffdec_lib/testdata/as3_new/src/tests/TestMetadata.as
+++ b/libsrc/ffdec_lib/testdata/as3_new/src/tests/TestMetadata.as
@@ -6,6 +6,7 @@ package tests
         [MyVarTag(var1 = "var 1", var2 = "var 2")]
         public var v:int = 5;
     
+        [MySingleTag("tag")]
 		public function run(): void
 		{
 			trace("hello");