Amend VST "MasterUpdateDisplay", allow UI(s) to idle-update.

diff --git a/libs/ardour/session_vst.cc b/libs/ardour/session_vst.cc
index 3252698bf4c3a8fece5f453f4c0e89b12a70725b..2720334ad588cd61e7b6edd8215754592f456e01 100644 (file)
--- a/libs/ardour/session_vst.cc
+++ b/libs/ardour/session_vst.cc
@@ -496,6 +496,10 @@ intptr_t Session::vst_callback (
                if (session) {
                        session->set_dirty ();
                }
+               /* allow plugin UI to update */
+#ifdef WINDOWS_VST_SUPPORT
+               fst_audio_master_idle();
+#endif
                return 0;
 
        case audioMasterBeginEdit: