No need to do the remove_theme_support
, just put yours in your functions.php
file, make sure its a different image (might sound obvious but just in case):
$custom_header_args = array(
'default-image' => get_theme_file_uri( '/assets/images/header.jpg' ),
'width' => 2000,
'height' => 1200,
'flex-height' => true,
'video' => true,
);
add_theme_support('custom-header', $custom_header_args);
the child theme
custom header theme_support
values will always override the values of the parent, its commented in the core:
// Merge in data from previous add_theme_support() calls.
// The first value registered wins. (A child theme is set up first.)
if ( isset( $_wp_theme_features['custom-header'] ) )
$args[0] = wp_parse_args( $_wp_theme_features['custom-header'][0], $args[0] );
the functions.php
of the child theme will run first (registering the theme support first) then the functions.php
of the parent.