--- a/LuaAPI.wiki	Tue Dec 04 00:03:52 2018 +0000
+++ b/LuaAPI.wiki	Tue Dec 04 00:05:30 2018 +0000
@@ -1439,7 +1439,7 @@
 -- Green example message.
 </code>
 
-=== <tt>!ShowMission(caption, subcaption, text, icon, time)</tt> ===
+=== <tt>!ShowMission(caption, subcaption, text, icon, time [, forceDisplay])</tt> ===
 This function will open the mission panel and set the texts in it.
 
 Use to tell the player what he/she is supposed to do. If you use this function, a mission panel is shown for the amount of time specified in `time` (in milliseconds). If `time` is set to 0, it will be displayed for a default amount of time.
@@ -1464,6 +1464,8 @@
 || `8` || Barrel ||
 || `9` || Dud mine ||
 
+If the optional parameter `forceDisplay` is `true`, this mission panel cannot be removed manually by the player. It's `false` by default.
+
 Example:
 <code language="lua">
 ShowMission(loc("Nobody Laugh"), loc("User Challenge"), loc("Eliminate the enemy before the time runs out"), 0, 0)