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Starting in HtmlFormEntry version 1.7.2, all tag handlers are required to implement a getAttributeDescriptors method. Attribute descriptors are used define what attributes a tag supports, to facilitate sharing tags via the metadata sharing module. When preparing a form for export, all metadata referenced by the form need to be included in the export package. For example, in the following tag, all the concepts referenced by id, uuid, or concept mapping need to be included in the export package:
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