diff --git a/tests/gumjs/script.c b/tests/gumjs/script.c
index 46fe89b31..61459eae8 100644
--- a/tests/gumjs/script.c
+++ b/tests/gumjs/script.c
@@ -5039,6 +5039,12 @@ TESTCASE (process_threads_have_names)
 
 TESTCASE (process_threads_have_user_time)
 {
+  GThread * thread;
+  GumThreadId thread_id;
+  volatile gboolean done = FALSE;
+
+  thread = create_sleeping_dummy_thread_sync (&done, &thread_id);
+
 #ifdef HAVE_LINUX
   if (!check_exception_handling_testable ())
     return;
@@ -5053,53 +5059,40 @@ TESTCASE (process_threads_have_user_time)
 #endif
 
 #if defined (HAVE_LINUX) && !defined (HAVE_ANDROID)
-  COMPILE_AND_LOAD_SCRIPT (
-      "function fibonacci(num) {"
-      "  if(num < 2) {"
-      "    return num;"
-      "  }"
-      "  else {"
-      "    return fibonacci(num-1) + fibonacci(num - 2);"
-      "  }"
-      "}"
-      "const tid = Process.getCurrentThreadId();"
-      "fibonacci(30);"
+    COMPILE_AND_LOAD_SCRIPT (
+      "Thread.sleep(0.25);"
       "const userTimeA = Process.enumerateThreads()"
-      "  .find(t => t.id == tid)"
+      "  .find(t => t.id == " GUM_PTR_CONST ")"
       "  .userTime;"
       "send(userTimeA != 0);"
-      "fibonacci(30);"
+      "Thread.sleep(0.25);"
       "const userTimeB = Process.enumerateThreads()"
-      "  .find(t => t.id == tid)"
+      "  .find(t => t.id == " GUM_PTR_CONST ")"
       "  .userTime;"
-      "send(userTimeB > userTimeA);"
-  );
+      "send(userTimeB > userTimeA);",
+      thread_id,
+      thread_id);
 #else
-  COMPILE_AND_LOAD_SCRIPT (
-      "function fibonacci(num) {"
-      "  if(num < 2) {"
-      "    return num;"
-      "  }"
-      "  else {"
-      "    return fibonacci(num-1) + fibonacci(num - 2);"
-      "  }"
-      "}"
-      "const tid = Process.getCurrentThreadId();"
-      "fibonacci(30);"
+    COMPILE_AND_LOAD_SCRIPT (
+      "Thread.sleep(0.25);"
       "const userTimeA = Process.enumerateThreads()"
-      "  .find(t => t.id == tid)"
+      "  .find(t => t.id == " GUM_PTR_CONST ")"
       "  .userTime;"
       "send(userTimeA == 0);"
-      "fibonacci(30);"
+      "Thread.sleep(0.25);"
       "const userTimeB = Process.enumerateThreads()"
-      "  .find(t => t.id == tid)"
+      "  .find(t => t.id == " GUM_PTR_CONST ")"
       "  .userTime;"
-      "send(userTimeB == 0);"
-  );
+      "send(userTimeB == 0);",
+      thread_id,
+      thread_id);
 #endif
 
   EXPECT_SEND_MESSAGE_WITH ("true");
   EXPECT_SEND_MESSAGE_WITH ("true");
+
+  done = TRUE;
+  g_thread_join (thread);
 }
 
 static gpointer