How can I set to different values to the recommended size the Heading Image. It is currently set at 978 px by 250 px. I would like to try it at 978×170
@Grafixer If you are talking about changing the size while uploading the header image then you can do it while uploading the header image. But if you are talking about changing the recommended size directly in the file then this is the file custom-header.php which is located inside theme folder->library folder->functions folder. Also make a child theme so that you wont loose the changes while you update the theme. hope this helps.
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