ADDED: support naked hyperlinks in tablecells and textboxes.

Also fix flickering due to IS_ROLLOVER flag getting
nuked.

Fixes https://gitlab.com/kicad/code/kicad/-/issues/18832

(cherry picked from commit 072d8d55fe)

common/string_utils.cpp

@@ -646,8 +646,8 @@ wxString RemoveHTMLTags( const wxString& aInput )
 
 wxString LinkifyHTML( wxString aStr )
 {
-    wxRegEx regex( wxS( "\\b(https?|ftp|file)://([-\\w+&@#/%?=~|!:,.;]*[^.,:;<>\\s\u00b6])" ),
-                   wxRE_ICASE );
+    static wxRegEx regex( wxS( "\\b(https?|ftp|file)://([-\\w+&@#/%?=~|!:,.;]*[^.,:;<>\\s\u00b6])" ),
+                          wxRE_ICASE );
 
     regex.ReplaceAll( &aStr, "<a href=\"\\0\">\\0</a>" );
 
@@ -655,6 +655,17 @@ wxString LinkifyHTML( wxString aStr )
 }
 
 
+bool IsURL( wxString aStr )
+{
+    static wxRegEx regex( wxS( "(https?|ftp|file)://([-\\w+&@#/%?=~|!:,.;]*[^.,:;<>\\s\u00b6])" ),
+                          wxRE_ICASE );
+
+    regex.ReplaceAll( &aStr, "<a href=\"\\0\">\\0</a>" );
+
+    return regex.Matches( aStr );
+}
+
+
 bool NoPrintableChars( const wxString& aString )
 {
     wxString tmp = aString;