diff --git a/emrun.py b/emrun.py
index 260bca19afc02..8804ab81af8a7 100644
--- a/emrun.py
+++ b/emrun.py
@@ -317,6 +317,8 @@ def create_emrun_safe_firefox_profile():
 user_pref("javascript.options.wasm_memory64", true);
 // Do not ask user consent to enable audio playback (0: Allow autoplay for all media)
 user_pref("media.autoplay.default", 0);
+// Enable JSPI support
+user_pref("javascript.options.wasm_js_promise_integration", true);
 ''')
     if emrun_options.private_browsing:
       f.write('''