tabs-macro: improve info about the "default" parameter (#5904)

editions/tw5.com/tiddlers/macros/TabsMacro.tid

@@ -1,9 +1,10 @@
 caption: tabs
 created: 20131228162203521
-modified: 20210525204556911
+modified: 20210721122823354
 tags: Macros [[Core Macros]]
 title: tabs Macro
 type: text/vnd.tiddlywiki
+
 The <<.def tabs>> [[macro|Macros]] presents a [[selection of tiddlers|Title Selection]] as a set of tabs that the user can switch between.
 
 The tabs display the <<.field caption>> field of a tiddler if it has one, or the tiddler's title otherwise. If specified, the tabs display the <<.field tooltip>> field of a tiddler as the respective button tooltip.
@@ -15,7 +16,7 @@ By default the tabs are arranged horizontally above the content. To get vertical
 ;tabsList
 : A [[filter|Filters]] selecting which tiddlers to include
 ;default
-: The title of the tiddler whose tab is to be selected by default
+: The title of the tiddler whose tab is to be selected by default, if the [[state tiddler|StateMechanism]] doesn't exist. The state tiddler takes precedence over this setting
 ;state
 : The prefix for the title of a [[state tiddler|StateMechanism]] for noting the currently selected tab, defaulting to `$:/state/tab`. It is recommended that this be a [[system tiddler|SystemTiddlers]]
 ;class