Obviously a long time since this was posted but I’ve had the same problem quite a lot, especially when it comes to icons for elements and making them editable by the client and using SVG.
I decided to have a crack at a solution. It’s not pretty but it works after the first time the SVG has been uploaded/chosen.
Stick in your functions.php;
function unleash_enqueue_scripts( $hook ) {
if( !in_array( $hook, array( 'post.php', 'post-new.php' ) ) )
return;
wp_enqueue_script(
'resizeSvg', // Handle
'/path/to/theme/js/resizeSVG.js', // Path to file
array( 'jquery' )
);
}
add_action( 'admin_enqueue_scripts', 'unleash_enqueue_scripts', 2000 );
Then create a file in your JS folder called resizeSVG.js and add in the following;
jQuery(document).ready(function() {
jQuery('.acf-image-image').each(function(){
if(jQuery(this).attr('src').indexOf('.svg') > 0) {
jQuery(this).css('width', '128px');
}
});
});
This basically resizes any acf-image that has .svg in it down to 128px, obviously you can change that as needed.