I have been struggling with some outlook specific tags being stripped off and I am out of options right now.
After looking into everything I could I finally when to the cache files to check if the tags were preserved and the answer is YES.
That means that everything is fine with the template up to the point when you send it.
So, something is happening when Mautic send the email, and I don't have any idea where should I start looking for a solution.
The tags being stripped of are these:
<head> ... <!--[if gte mso 9]> <xml> <o:OfficeDocumentSettings> <o:AllowPNG></o:AllowPNG> <o:PixelsPerInch>96</o:PixelsPerInch> </o:OfficeDocumentSettings> </xml> <![endif]--> </head>
<!--[if gte mso 9]> <v:rect xmlns:v="urn:schemas-microsoft-com:vml" fill="true" stroke="false" style="width:300px;height:210px;"> <v:fill type="tile" src="https://i.imgur.com/YJOX1PC.png" color="#7bceeb" ></v:fill> <v:textbox inset="0,0,0,0"> <![endif]-->
Any idea of possible source files I should be looking at helps right now.