In a header, footer, or text object, if you select all text in a paragraph and apply a background color, that color appears the full width of the dialog box and in the viewed report, even if the last line of text is short. This is expected behavior for HTML output. Here is an example.

As a workaround, type a space after the last period in the paragraph. Then, do not include the space when selecting text for the background color. In the following example, there is a space after the period that was not selected when applying the background color.

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