diff --git a/src/WebAssembly/FreeCADCoreProbe/CMakeLists.txt b/src/WebAssembly/FreeCADCoreProbe/CMakeLists.txt
index 9adfc1f8..8bfbcc79 100644
--- a/src/WebAssembly/FreeCADCoreProbe/CMakeLists.txt
+++ b/src/WebAssembly/FreeCADCoreProbe/CMakeLists.txt
@@ -699,10 +699,10 @@ endif()
 if(BUILD_MESH_PART)
     add_executable(FreeCADWebMeshPartRuntimeProbe MeshPartRuntimeProbe.cpp)
     target_compile_features(FreeCADWebMeshPartRuntimeProbe PRIVATE cxx_std_17)
-target_compile_options(FreeCADWebMeshPartRuntimeProbe PRIVATE "-O2" "-g0" "-fexceptions" "-pthread")
+    target_compile_options(FreeCADWebMeshPartRuntimeProbe PRIVATE "-O2" "-g0" "-fexceptions" "-pthread" "-sUSE_PTHREADS=1" "-sPTHREAD_POOL_SIZE=4")
     target_include_directories(FreeCADWebMeshPartRuntimeProbe PRIVATE "${CMAKE_BINARY_DIR}" "${CMAKE_BINARY_DIR}/src" "${CMAKE_SOURCE_DIR}/src")
     target_link_libraries(FreeCADWebMeshPartRuntimeProbe PRIVATE MeshPart Materials ${Python3_LIBRARIES} "${_freecad_web_python_build}/Modules/_decimal/libmpdec/libmpdec.a" "${_freecad_web_python_build}/Modules/_hacl/libHacl_Hash_SHA2.a" "${_freecad_web_python_build}/Modules/expat/libexpat.a")
-target_link_options(FreeCADWebMeshPartRuntimeProbe PRIVATE "-O2" "-g0" "--no-entry" "-pthread" "-sUSE_PTHREADS=1" "-sWASM=1" "-sMODULARIZE=1" "-sEXPORT_ES6=1" "-sEXPORT_NAME=FreeCADWebMeshPartRuntimeProbe" "-sALLOW_MEMORY_GROWTH=1" "-sINITIAL_MEMORY=33554432" "-sENVIRONMENT=web,worker,node" "-sUSE_BZIP2=1" "-sDISABLE_EXCEPTION_CATCHING=0" "-sEXPORTED_RUNTIME_METHODS=['ccall']" "--embed-file=${_freecad_web_python_encodings}@/freecad-python/encodings")
+    target_link_options(FreeCADWebMeshPartRuntimeProbe PRIVATE "-O2" "-g0" "--no-entry" "-pthread" "-sUSE_PTHREADS=1" "-sPTHREAD_POOL_SIZE=4" "-sWASM=1" "-sMODULARIZE=1" "-sEXPORT_ES6=1" "-sEXPORT_NAME=FreeCADWebMeshPartRuntimeProbe" "-sALLOW_MEMORY_GROWTH=1" "-sINITIAL_MEMORY=33554432" "-sENVIRONMENT=web,worker,node" "-sUSE_BZIP2=1" "-sDISABLE_EXCEPTION_CATCHING=0" "-sEXPORTED_RUNTIME_METHODS=['ccall']" "--embed-file=${_freecad_web_python_encodings}@/freecad-python/encodings")
     set_target_properties(FreeCADWebMeshPartRuntimeProbe PROPERTIES SUFFIX ".js" RUNTIME_OUTPUT_DIRECTORY "${CMAKE_BINARY_DIR}/bin")
 endif()