--- a/svghmi/svghmi.c	Mon Oct 28 19:52:43 2019 +0100
+++ b/svghmi/svghmi.c	Tue Oct 29 09:10:10 2019 +0100
@@ -175,6 +175,7 @@
     while(AtomicCompareExchange(&dsc->wlock, 0, 1)) sched_yield();
     dsc->refresh_period_ms = refresh_period_ms;
     if(refresh_period_ms) {
+        /* TODO : maybe only if was null before for optimization */
         dsc->wstate = buf_new;
     } else {
         dsc->wstate = buf_free;