Add AVIF support

src/js/_enqueues/vendor/plupload/handlers.js

@@ -610,6 +610,11 @@ jQuery( document ).ready( function( $ ) {
 					wpQueueError( pluploadL10n.noneditable_image );
 					up.removeFile( file );
 					return;
+				} else if ( file.type === 'image/avif' && up.settings.avif_upload_error ) {
+					// Disallow uploading of AVIF images if the server cannot edit them.
+					wpQueueError( pluploadL10n.noneditable_image );
+					up.removeFile( file );
+					return;
 				}
 
 				fileQueued( file );

src/js/_enqueues/vendor/plupload/wp-plupload.js

@@ -363,6 +363,11 @@ window.wp = window.wp || {};
 					error( pluploadL10n.noneditable_image, {}, file, 'no-retry' );
 					up.removeFile( file );
 					return;
+				} else if ( file.type === 'image/avif' && up.settings.avif_upload_error ) {
+					// Disallow uploading of AVIF images if the server cannot edit them.
+					error( pluploadL10n.noneditable_image, {}, file, 'no-retry' );
+					up.removeFile( file );
+					return;
 				}
 
 				// Generate attributes for a new `Attachment` model.

src/js/_enqueues/vendor/thickbox/thickbox.js

@@ -76,15 +76,16 @@ function tb_show(caption, url, imageGroup) {//function called when the user clic
 	   		baseURL = url;
 	   }
 
-	   var urlString = /\.jpg$|\.jpeg$|\.png$|\.gif$|\.bmp$|\.webp$/;
+	   var urlString = /\.jpg$|\.jpeg$|\.png$|\.gif$|\.bmp$|\.webp$|\.avif$/;
 	   var urlType = baseURL.toLowerCase().match(urlString);
 
 		if(urlType == '.jpg' ||
 			urlType == '.jpeg' ||
 			urlType == '.png' ||
 			urlType == '.gif' ||
 			urlType == '.bmp' ||
-			urlType == '.webp'
+			urlType == '.webp' ||
+			urlType == '.avif'
 		){//code to show images
 
 			TB_PrevCaption = "";

src/js/media/controllers/library.js

@@ -196,7 +196,7 @@ Library = wp.media.controller.State.extend(/** @lends wp.media.controller.Librar
 	isImageAttachment: function( attachment ) {
 		// If uploading, we know the filename but not the mime type.
 		if ( attachment.get('uploading') ) {
-			return /\.(jpe?g|png|gif|webp)$/i.test( attachment.get('filename') );
+			return /\.(jpe?g|png|gif|webp|avif)$/i.test( attachment.get('filename') );
 		}
 
 		return attachment.get('type') === 'image';

src/wp-admin/includes/image-edit.php

@@ -387,6 +387,12 @@ function wp_stream_image( $image, $mime_type, $attachment_id ) {
 					return imagewebp( $image, null, 90 );
 				}
 				return false;
+			case 'image/avif':
+				if ( function_exists( 'imageavif' ) ) {
+					header( 'Content-Type: image/avif' );
+					return imageavif( $image, null, 90 );
+				}
+			return false;
 			default:
 				return false;
 		}
@@ -491,6 +497,11 @@ function wp_save_image_file( $filename, $image, $mime_type, $post_id ) {
 					return imagewebp( $image, $filename );
 				}
 				return false;
+			case 'image/avif':
+				if ( function_exists( 'imageavif' ) ) {
+					return imageavif( $image, $filename );
+				}
+				return false;
 			default:
 				return false;
 		}

src/wp-admin/includes/media.php

@@ -2194,6 +2194,11 @@ function media_upload_form( $errors = null ) {
 		$plupload_init['webp_upload_error'] = true;
 	}
 
+	// Check if AVIF images can be edited.
+	if ( ! wp_image_editor_supports( array( 'mime_type' => 'image/avif' ) ) ) {
+		$plupload_init['avif_upload_error'] = true;
+	}
+
 	/**
 	 * Filters the default Plupload settings.
 	 *

src/wp-admin/includes/schema.php

@@ -1247,6 +1247,7 @@ function populate_network_meta( $network_id, array $meta = array() ) {
 		'png',
 		'gif',
 		'webp',
+		'avif',
 		// Video.
 		'mov',
 		'avi',