U4-3710, -3732 - Fix default ShortStringHelper

src/Umbraco.Core/StringExtensions.cs

@@ -801,9 +801,11 @@ namespace Umbraco.Core
                 if (_helper != null)
                     return _helper;
 
-                // there *has* to be a short string helper, even if the resolver has not
-                // been initialized - used the default one with default configuration.
-                _helper = new DefaultShortStringHelper().WithConfig(allowLeadingDigits: true);
+                // we don't want Umbraco to die because the resolver hasn't been initialized
+                // as the ShortStringHelper is too important, so as long as it's not there
+                // already, we use a default one. That should never happen, but...
+                Logging.LogHelper.Warn<IShortStringHelper>("ShortStringHelperResolver.HasCurrent == false, fallback to default.");
+                _helper = new DefaultShortStringHelper().WithDefaultConfig();
                 _helper.Freeze();
                 return _helper;
             }