PHP Warning: Illegal string offset ‘height’ / ‘width’

Hi! I’m using PHP 7.1, WP 5.0.2 and Avada theme. I realized that in some cases (I’m not which ones), the error log is showing me errors with the size of some svg images:

PHP Warning:  Illegal string offset 'width' in /blablabla/wp-includes/media.php on line 988
PHP Warning:  Illegal string offset 'height' in /blablabla/wp-includes/media.php on line 989

I fixed it with a custom function in my child theme (a filter to modify the returned value in wp-includes/post.php => wp_get_attachment_metadata()) that simply returns false when some of these properties are not present:

 14 function wp_get_attachment_metadata_mine($data) {
 15 
 16     $res = $data;
 17     if (!isset($data['width']) || !isset($data['height'])) {
 18         $res = false;
 19     }
 20 
 21     return $res;                                                                                                                                                            
 22 }
 23 add_filter( 'wp_get_attachment_metadata' , 'wp_get_attachment_metadata_mine' );

I saw this error in some other sites (of mine), so I was wondering if you could “fix” this in some way in your plugin. I’m not a WP dev so I’m not sure it’s possible.

Thanks!