Tripled curly braces delimit “filtered transclusion” syntax.
Thus, {{{No}}} is a filter containing literal text “No”, and {{{Description}}} is a filter containing literal text “Description”
To transclude field values, use DOUBLED curly braces around !!fieldname references, like this:
caption: {{!!No}} {{!!Description}}
Note that these transcluded field references depend upon the value of currentTiddler, so it will only give the correct result when currentTiddler is “New Tiddler_1”. To ensure that the caption is always correct, you may need to include the tiddler title in the reference, like this:
caption: {{New Tiddler_1!!No}} {{New Tiddler_1!!Description}}
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