ES-999797-Feedback addressed

Author: Kathiresan4347

Document-Processing/Word/Word-Library/NET/html.md

@@ -251,6 +251,9 @@ N> Calling the above event is mandatory in ASP.NET Core, UWP, and Xamarin platfo
 ### Supported CSS Selector in DocIO
 
 CSS selectors are used to select the HTML elements you want to style and apply a set of CSS rules.
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+N> DocIO supports only internally defined CSS selectors during HTML conversion and does not support external CSS selectors referenced in the HTML file.
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 <table>
 <tr>
     <td><strong>Selectors</strong></td>