Media: improve error messages for unsupported uploads.

Improve language explaining the reason for failure when uploading a modern image format like WebP or AVIF that the server doesn’t handle.

Props adamsilverstein, Cybr.
Fixes #61361.



git-svn-id: https://develop.svn.wordpress.org/trunk@59590 602fd350-edb4-49c9-b593-d223f7449a82

Author: adamsilverstein

src/wp-includes/script-loader.php

@@ -983,7 +983,7 @@ function wp_default_scripts( $scripts ) {
 		/* translators: %s: File name. */
 		'file_exceeds_size_limit'   => __( '%s exceeds the maximum upload size for this site.' ),
 		'zero_byte_file'            => __( 'This file is empty. Please try another.' ),
-		'invalid_filetype'          => __( 'Sorry, you are not allowed to upload this file type.' ),
+		'invalid_filetype'          => __( 'This file cannot be processed by the web server.' ),
 		'not_an_image'              => __( 'This file is not an image. Please try another.' ),
 		'image_memory_exceeded'     => __( 'Memory exceeded. Please try another smaller file.' ),
 		'image_dimensions_exceeded' => __( 'This is larger than the maximum size. Please try another.' ),
@@ -1007,7 +1007,7 @@ function wp_default_scripts( $scripts ) {
 		/* translators: %s: File name. */
 		'error_uploading'           => __( '“%s” has failed to upload.' ),
 		'unsupported_image'         => __( 'This image cannot be displayed in a web browser. For best results convert it to JPEG before uploading.' ),
-		'noneditable_image'         => __( 'This image cannot be processed by the web server. Convert it to JPEG or PNG before uploading.' ),
+		'noneditable_image'         => __( 'The web server cannot generate responsive image sizes for this image. Convert it to JPEG or PNG before uploading.' ),
 		'file_url_copied'           => __( 'The file URL has been copied to your clipboard' ),
 	);