Fix tags not animating in viewtemplate (#4142)

* fix tags not animating in viewtemplate

this PR uses the addprefix removesuffix filters, not a new filter as proposed in #3763

* use new `then` operator

core/ui/ViewTemplate.tid

@@ -1,11 +1,8 @@
 title: $:/core/ui/ViewTemplate
 
-\define frame-classes()
-tc-tiddler-frame tc-tiddler-view-frame $(missingTiddlerClass)$ $(shadowTiddlerClass)$ $(systemTiddlerClass)$ $(tiddlerTagClasses)$ $(userClass)$
-\end
 \define folded-state()
 $:/state/folded/$(currentTiddler)$
 \end
-<$vars storyTiddler=<<currentTiddler>> tiddlerInfoState=<<qualify "$:/state/popup/tiddler-info">> userClass={{!!class}}><$tiddler tiddler=<<currentTiddler>>><div data-tiddler-title=<<currentTiddler>> data-tags={{!!tags}} class=<<frame-classes>>><$list filter="[all[shadows+tiddlers]tag[$:/tags/ViewTemplate]!has[draft.of]]" variable="listItem"><$transclude tiddler=<<listItem>>/></$list>
+<$vars storyTiddler=<<currentTiddler>> tiddlerInfoState=<<qualify "$:/state/popup/tiddler-info">>><div data-tiddler-title=<<currentTiddler>> data-tags={{!!tags}} class={{{ tc-tiddler-frame tc-tiddler-view-frame [<currentTiddler>is[tiddler]then[tc-tiddler-exists]] [<currentTiddler>is[missing]!is[shadow]then[tc-tiddler-missing]] [<currentTiddler>is[shadow]then[tc-tiddler-exists tc-tiddler-shadow]] [<currentTiddler>is[system]then[tc-tiddler-system]] [{!!class}] [<currentTiddler>tags[]encodeuricomponent[]addprefix[tc-tagged-]] +[join[ ]] }}}><$list filter="[all[shadows+tiddlers]tag[$:/tags/ViewTemplate]!has[draft.of]]" variable="listItem"><$transclude tiddler=<<listItem>>/></$list>
 </div>
-</$tiddler></$vars>
+</$vars>