-cp target/wasm32-unknown-emscripten/release/mandelwow.js .
-cp target/wasm32-unknown-emscripten/release/deps/mandelwow-*.{wasm,data} .
+cp -a target/wasm32-unknown-emscripten/release/mandelwow.js .
+cp -a target/wasm32-unknown-emscripten/release/deps/mandelwow-*.{wasm,data} .