UI: Only defer property updates for input and transition sources

Deferring properties was only ever made for input and transition
sources. As other property dialogs do not have an "Ok" button that would
cause an update to happen, if the deferred flag was set the callback
would never be called.
Also clarifies the docs to reflect this.

UI/properties-view.cpp

@@ -88,19 +88,33 @@ Q_DECLARE_METATYPE(media_frames_per_second);
 
 void OBSPropertiesView::ReloadProperties()
 {
+	deferUpdate = false;
 	if (weakObj || rawObj) {
 		OBSObject strongObj = GetObject();
 		void *obj = strongObj ? strongObj.Get() : rawObj;
-		if (obj)
+		if (obj) {
 			properties.reset(reloadCallback(obj));
+
+			if (obs_obj_get_type(obj) == OBS_OBJ_TYPE_SOURCE) {
+				enum obs_source_type type = obs_source_get_type(
+					(obs_source_t *)obj);
+				if (type == OBS_SOURCE_TYPE_INPUT ||
+				    type == OBS_SOURCE_TYPE_TRANSITION) {
+					uint32_t flags =
+						obs_properties_get_flags(
+							properties.get());
+					deferUpdate =
+						(flags &
+						 OBS_PROPERTIES_DEFER_UPDATE) !=
+						0;
+				}
+			}
+		}
 	} else {
 		properties.reset(reloadCallback((void *)type.c_str()));
 		obs_properties_apply_settings(properties.get(), settings);
 	}
 
-	uint32_t flags = obs_properties_get_flags(properties.get());
-	deferUpdate = (flags & OBS_PROPERTIES_DEFER_UPDATE) != 0;
-
 	RefreshProperties();
 }
 

docs/sphinx/reference-properties.rst

@@ -51,7 +51,9 @@ General Functions
                  - OBS_PROPERTIES_DEFER_UPDATE - A hint that tells the
                    front-end to defers updating the settings until the
                    user has finished editing all properties rather than
-                   immediately updating any settings
+                   immediately updating any settings. Currently only
+                   works for properties of input and transition sources,
+                   this flag is a no-op for other properties at this time.
 
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