--- mozc/src/unix/ibus/property_handler.cc
+++ mozc/src/unix/ibus/property_handler.cc
@@ -40,6 +40,8 @@
 #include "unix/ibus/mozc_engine_property.h"
 #include "unix/ibus/path_util.h"
 
+#include <cstdlib>
+
 // On Gnome Shell with IBus 1.5, new property named "symbol" is used to
 // represent the mode indicator on the system panel. Note that "symbol" does
 // not exist in IBus 1.4.x.
@@ -80,7 +82,7 @@ bool GetDisabled(IBusEngine *engine) {
 // On IBus 1.4.x, IBus expects that an IME should always be turned on and
 // IME on/off keys are handled by IBus itself rather than each IME.
 #if IBUS_CHECK_VERSION(1, 5, 0)
-const bool kActivatedOnLaunch = false;
+const bool kActivatedOnLaunch = !!::std::getenv("IBUS_MOZC_DEFAULT_HIRAGANA");
 #else
 const bool kActivatedOnLaunch = true;
 #endif  // IBus>=1.5.0
