When underline style is already applied to a text, the style cannot be changed from the Font Properties dialog. Workaround: Use the dropdown button in the ribbon. Steps to reproduce: - Select text. - Open FontPropertiesDialog (or use ribbonButton for Undelinetext) and set underline style "Line". - Submit the dialog. - Right-click on the selected text again. - Choose "Font..." from the context menu to open FontProperties dialog again. - Change the underline style. - Submit the dialog. Expected: The selected underline style should be applied. Actual: There is no applied underline style on the text. Fix available in R3 2018 SP1 release.