FreeMarker syntax is invalid.

Can't convert boolean to string automatically, because the "boolean_format" setting was "true,false", which is the legacy deprecated default, and we treat it as if no format was set. This is the default configuration; you should provide the format explicitly for each place where you print a boolean.

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Tip: Write something like myBool?string('yes', 'no') to specify boolean formatting in place.
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Tip: If you want "true"/"false" result as you are generating computer-language output (not for direct human consumption), then use "?c", like ${myBool?c}. (If you always generate computer-language output, then it's might be reasonable to set the "boolean_format" setting to "c" instead.)
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Tip: If you need the same two values on most places, the programmers can set the "boolean_format" setting to something like "yes,no". However, then it will be easy to unwillingly format booleans like that.
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FTL stack trace ("~" means nesting-related):
- Failed at: ${desc?has_content && desc?length > 2} [in template "template_id" at line 27, column 1]
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