diff --git a/javascript/extractor/src/com/semmle/jcorn/CustomParser.java b/javascript/extractor/src/com/semmle/jcorn/CustomParser.java
index b0f347d53c9..ab7f7faef6b 100644
--- a/javascript/extractor/src/com/semmle/jcorn/CustomParser.java
+++ b/javascript/extractor/src/com/semmle/jcorn/CustomParser.java
@@ -217,7 +217,7 @@ public class CustomParser extends FlowParser {
 	protected INode parseFunction(Position startLoc, boolean isStatement, boolean allowExpressionBody, boolean isAsync) {
 		if (isFunctionSent(isStatement))
 			return super.parseFunction(startLoc, isStatement, allowExpressionBody, isAsync);
-		allowExpressionBody = allowExpressionBody || options.mozExtensions() && !isStatement;
+		allowExpressionBody = allowExpressionBody || options.mozExtensions();
 		boolean oldInGen = this.inGenerator, oldInAsync = this.inAsync;
 		int oldYieldPos = this.yieldPos, oldAwaitPos = this.awaitPos;
 		Pair<Boolean, Identifier> p = parseFunctionName(isStatement, isAsync);
diff --git a/javascript/extractor/src/com/semmle/jcorn/Parser.java b/javascript/extractor/src/com/semmle/jcorn/Parser.java
index b28b02fc7ed..b8207d19e83 100644
--- a/javascript/extractor/src/com/semmle/jcorn/Parser.java
+++ b/javascript/extractor/src/com/semmle/jcorn/Parser.java
@@ -2991,7 +2991,7 @@ public class Parser {
 		IFunction node;
 		SourceLocation loc = new SourceLocation(startLoc);
 		if (isStatement && id != null)
-			node = new FunctionDeclaration(loc, id, params, (BlockStatement) body, generator, async);
+			node = new FunctionDeclaration(loc, id, params, body, generator, async);
 		else
 			node = new FunctionExpression(loc, id, params, body, generator, async);
 		return this.finishNode(node);
diff --git a/javascript/extractor/src/com/semmle/js/ast/FunctionDeclaration.java b/javascript/extractor/src/com/semmle/js/ast/FunctionDeclaration.java
index 4971aa671dc..1fbc7e0702d 100644
--- a/javascript/extractor/src/com/semmle/js/ast/FunctionDeclaration.java
+++ b/javascript/extractor/src/com/semmle/js/ast/FunctionDeclaration.java
@@ -17,26 +17,26 @@ import com.semmle.ts.ast.TypeParameter;
  * </pre>
  */
 public class FunctionDeclaration extends Statement implements IFunction {
-	private final AFunction<BlockStatement> fn;
+	private final AFunction<? extends Node> fn;
 	private final boolean hasDeclareKeyword;
 	private int symbol = -1;
 
-	public FunctionDeclaration(SourceLocation loc, Identifier id, List<Expression> params, BlockStatement body, boolean generator,
+	public FunctionDeclaration(SourceLocation loc, Identifier id, List<Expression> params, Node body, boolean generator,
 			boolean async) {
-		this(loc, new AFunction<BlockStatement>(id, params, body, generator, async, Collections.emptyList(), Collections.emptyList(),
+		this(loc, new AFunction<>(id, params, body, generator, async, Collections.emptyList(), Collections.emptyList(),
 				Collections.emptyList(), null, null),
 				false);
 	}
 
 	public FunctionDeclaration(SourceLocation loc, Identifier id,
-			List<Expression> params, BlockStatement body, boolean generator, boolean async, boolean hasDeclareKeyword,
+			List<Expression> params, Node body, boolean generator, boolean async, boolean hasDeclareKeyword,
 			List<TypeParameter> typeParameters, List<ITypeExpression> parameterTypes, ITypeExpression returnType,
 			ITypeExpression thisParameterType) {
-		this(loc, new AFunction<BlockStatement>(id, params, body, generator, async, typeParameters, parameterTypes, Collections.emptyList(),
+		this(loc, new AFunction<>(id, params, body, generator, async, typeParameters, parameterTypes, Collections.emptyList(),
 				returnType, thisParameterType), hasDeclareKeyword);
 	}
 
-	private FunctionDeclaration(SourceLocation loc, AFunction<BlockStatement> fn, boolean hasDeclareKeyword) {
+	private FunctionDeclaration(SourceLocation loc, AFunction<Node> fn, boolean hasDeclareKeyword) {
 		super("FunctionDeclaration", loc);
 		this.fn = fn;
 		this.hasDeclareKeyword = hasDeclareKeyword;
@@ -56,7 +56,7 @@ public class FunctionDeclaration extends Statement implements IFunction {
 	@Override public boolean hasDefault(int i)     { return fn.hasDefault(i);  }
 	@Override public Expression getDefault(int i)  { return fn.getDefault(i);  }
 	@Override public IPattern getRest()            { return fn.getRest();      }
-	@Override public BlockStatement getBody()      { return fn.getBody();      }
+	@Override public Node getBody()                { return fn.getBody();      }
 	@Override public boolean hasRest()             { return fn.hasRest();      }
 	public boolean hasId()                         { return fn.hasId();        }
 	public boolean isGenerator()                   { return fn.isGenerator();  }
diff --git a/javascript/extractor/tests/mozilla/input/exprfns.js b/javascript/extractor/tests/mozilla/input/exprfns.js
new file mode 100644
index 00000000000..434f0c84e50
--- /dev/null
+++ b/javascript/extractor/tests/mozilla/input/exprfns.js
@@ -0,0 +1,7 @@
+function f(x)("result")
+
+function(b) {
+  if (b) {
+    function g(y)("other result")
+  }
+}
diff --git a/javascript/extractor/tests/mozilla/output/trap/exprfns.js.trap b/javascript/extractor/tests/mozilla/output/trap/exprfns.js.trap
new file mode 100644
index 00000000000..6092fdc9e59
--- /dev/null
+++ b/javascript/extractor/tests/mozilla/output/trap/exprfns.js.trap
@@ -0,0 +1,437 @@
+#10000=@"/exprfns.js;sourcefile"
+files(#10000,"/exprfns.js","exprfns","js",0)
+#10001=@"/;folder"
+folders(#10001,"/","")
+containerparent(#10001,#10000)
+#10002=@"loc,{#10000},0,0,0,0"
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+hasLocation(#10000,#10002)
+#20000=@"global_scope"
+scopes(#20000,0)
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+#20002=*
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+")
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+locations_default(#20005,#10000,2,1,2,0)
+hasLocation(#20004,#20005)
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+hasLocation(#20006,#20007)
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+hasLocation(#20075,#20003)
+stmtContainers(#20075,#20001)
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+")
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+")
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+")
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+")
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