Panel:SetFontInternal
Example
Sets the font of a RichText element to match the chat box font.
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Sets the font used to render this panel's text. This works for Label, TextEntry and RichText, but it's a better idea to use their local SetFont
(DTextEntry:SetFont, DLabel:SetFont) methods when available.
To retrieve the font used by a panel, call Panel:GetFont.
See here for a list of existing fonts. Alternatively, use surface.CreateFont to create your own custom font.
Sets the font of a RichText element to match the chat box font.