diff --git a/WebConverter/WebConverter.csproj b/WebConverter/WebConverter.csproj
index 1579b71..fbcfa46 100644
--- a/WebConverter/WebConverter.csproj
+++ b/WebConverter/WebConverter.csproj
@@ -36,11 +36,11 @@
   </PropertyGroup>
 
   <PropertyGroup Condition="'$(Configuration)'=='Debug'">
-    <EmccCompileOptimizationFlag>-O0 -g3 -s ASSERTIONS=2 -s SAFE_HEAP=0 -s STACK_OVERFLOW_CHECK=1 -s DEMANGLE_SUPPORT=1</EmccCompileOptimizationFlag>
+    <EmccCompileOptimizationFlag>-O0 -g3 -s ASSERTIONS=2 -s SAFE_HEAP=0 -s STACK_OVERFLOW_CHECK=1</EmccCompileOptimizationFlag>
   </PropertyGroup>
 
   <PropertyGroup Condition="'$(Configuration)'!='Debug'">
-    <EmccCompileOptimizationFlag>-Oz -g0 -s ASSERTIONS=0 -s SAFE_HEAP=0 -s STACK_OVERFLOW_CHECK=0 -s DEMANGLE_SUPPORT=0</EmccCompileOptimizationFlag>
+    <EmccCompileOptimizationFlag>-Oz -g0 -s ASSERTIONS=0 -s SAFE_HEAP=0 -s STACK_OVERFLOW_CHECK=0</EmccCompileOptimizationFlag>
   </PropertyGroup>
 
   <ItemGroup>