I just need to add a custom text and a logo to my print layout A3/A4 Landscape/Portrait.
Is it possible? If yes, how should I do to modify Print Widget.
It is possible but it is not a modification of the print widget it requires you to use the print service on your ArcGIS Server (not esri's print service) and then you can edit the defult template on your server to add the logo and custom text.
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