You can insert tags in the frames of the library objects. Have in mind that when you link such frames to article elements, the text of the article element will be by default added in the next paragraph, and not in the paragraph with the style.

Therefore, the style will actually not be effective, until you enter in the text, and then join the style paragraph with the text paragraph. On the following screenshot, the article element text is merged in a new paragraph below the style:

Deleting the extra end of paragraph, the style will become effective:

To avoid such problem, add NewLineOnMerge="false" to the <EditorialConfig node. If the value does not exist in the EditorialConfig, the default is true. Therefore, when joining a local text with a linked text, the linked text is inserted in a new paragraph. Set to false to insert it in the same paragraph.