diff --git a/php/class-assets.php b/php/class-assets.php
index 9315bbe5b..6ece25e45 100644
--- a/php/class-assets.php
+++ b/php/class-assets.php
@@ -355,24 +355,6 @@ public function add_url_replacements() {
 			wp_safe_redirect( $referrer );
 			exit;
 		}
-		if ( ! empty( $this->delivery->known ) ) {
-
-			foreach ( $this->delivery->known as $url => $set ) {
-				if ( is_int( $set ) || empty( $set['public_id'] ) ) {
-					continue;
-				}
-				$public_id = $set['public_id'];
-				if ( ! empty( $set['format'] ) ) {
-					$public_id .= '.' . $set['format'];
-				}
-				$cloudinary_url = $this->media->cloudinary_url( $set['post_id'], array( $set['width'], $set['height'] ), null, $public_id );
-				if ( $cloudinary_url ) {
-					// Late replace on unmatched urls (links, inline styles etc..), both http and https.
-					String_Replace::replace( 'http:' . $url, $cloudinary_url );
-					String_Replace::replace( 'https:' . $url, $cloudinary_url );
-				}
-			}
-		}
 	}
 
 	/**
diff --git a/php/class-delivery.php b/php/class-delivery.php
index 7ad07395b..8a0e87f3d 100644
--- a/php/class-delivery.php
+++ b/php/class-delivery.php
@@ -201,7 +201,7 @@ public function filter_out_cloudinary( $content ) {
 			$transformations = $this->media->get_transformations_from_string( $original_url );
 
 			if ( 'image' === $this->media->get_resource_type( $result['post_id'] ) ) {
-				$attachment_url  = wp_get_attachment_image_url( $result['post_id'], $size );
+				$attachment_url = wp_get_attachment_image_url( $result['post_id'], $size );
 			} else {
 				$attachment_url = wp_get_attachment_url( $result['post_id'] );
 			}
@@ -567,7 +567,7 @@ protected function setup_hooks() {
 		// Add filters.
 		add_filter( 'content_save_pre', array( $this, 'filter_out_cloudinary' ) );
 		add_action( 'save_post', array( $this, 'remove_replace_cache' ) );
-		add_action( 'cloudinary_string_replace', array( $this, 'catch_urls' ) );
+		add_action( 'cloudinary_string_replace', array( $this, 'catch_urls' ), 10, 2 );
 		add_filter( 'post_thumbnail_html', array( $this, 'process_featured_image' ), 100, 3 );
 
 		add_filter( 'cloudinary_current_post_id', array( $this, 'get_current_post_id' ) );
@@ -669,6 +669,12 @@ public function setup() {
 	 */
 	protected function init_delivery() {
 
+		// Reset internals.
+		$this->known      = array();
+		$this->unknown    = array();
+		$this->found_urls = array();
+		$this->unusable   = array();
+
 		add_filter( 'wp_calculate_image_srcset', array( $this->media, 'image_srcset' ), 10, 5 );
 
 		/**
@@ -807,7 +813,6 @@ protected function get_context_cache() {
 	 */
 	public function get_media_tags( $content, $tags = 'img|video' ) {
 		$images = array();
-		$urls   = '';
 		if ( preg_match_all( '#(?P<tags><(' . $tags . ')[^>]*\>){1}#is', $content, $found ) ) {
 			$count = count( $found[0] );
 			for ( $i = 0; $i < $count; $i ++ ) {
@@ -822,16 +827,17 @@ public function get_media_tags( $content, $tags = 'img|video' ) {
 	 * Convert media tags from Local to Cloudinary, and register with String_Replace.
 	 *
 	 * @param string $content The HTML to find tags and prep replacement in.
+	 * @param string $context The content of the content.
 	 *
 	 * @return array
 	 */
-	public function convert_tags( $content ) {
+	public function convert_tags( $content, $context = 'view' ) {
 		$has_cache = $this->get_context_cache();
 		$type      = is_ssl() ? 'https' : 'http';
 		if ( Utils::is_amp() ) {
 			$type = 'amp';
 		}
-		if ( ! empty( $has_cache[ $type ] ) ) {
+		if ( 'view' === $context && ! empty( $has_cache[ $type ] ) ) {
 			$cached = $has_cache[ $type ];
 		}
 
@@ -863,29 +869,50 @@ public function convert_tags( $content ) {
 				continue;
 			}
 			$this->current_post_id = $set['context'];
-			// Use cached item if found.
-			if ( isset( $cached[ $set['original'] ] ) ) {
-				$replacements[ $set['original'] ] = $cached[ $set['original'] ];
-			} else {
-				// Register replacement.
-				$replacements[ $set['original'] ] = $this->rebuild_tag( $set );
+
+			// We only rebuild tags in the view context.
+			if ( 'view' === $context ) {
+				// Use cached item if found.
+				if ( isset( $cached[ $set['original'] ] ) ) {
+					$replacements[ $set['original'] ] = $cached[ $set['original'] ];
+				} else {
+					// Register replacement.
+					$replacements[ $set['original'] ] = $this->rebuild_tag( $set );
+				}
 			}
 			$this->current_post_id = null;
 
-			// Check for src aliases.
-			if ( isset( $this->found_urls[ $set['base_url'] ] ) ) {
-				$base = dirname( $set['base_url'] );
-				foreach ( $this->found_urls[ $set['base_url'] ] as $size => $file_name ) {
-					$local_url = $type . ':' . path_join( $base, $file_name );
-					if ( isset( $cached[ $local_url ] ) ) {
-						$aliases[ $local_url ] = $cached[ $local_url ];
-						continue;
-					}
-					$cloudinary_url        = $this->media->cloudinary_url( $set['id'], explode( 'x', $size ), $set['transformations'], $set['atts']['data-public-id'], $set['overwrite_transformations'] );
-					$aliases[ $local_url ] = $cloudinary_url;
+		}
+
+		// Create aliases for urls where were found, but not found with an ID in a tag.
+		// Create the Full/Scaled items first.
+		foreach ( $this->known as $url => $relation ) {
+			if ( $url === $relation['public_id'] ) {
+				continue; // We don't need the public_id relation item.
+			}
+			$base             = $type . ':' . $url;
+			$public_id        = ! is_admin() ? $relation['public_id'] . '.' . $relation['format'] : null;
+			$aliases[ $base ] = $this->media->cloudinary_url( $relation['post_id'], array(), $relation['transformations'], $public_id );
+		}
+
+		// Create the sized found relations second.
+		foreach ( $this->found_urls as $url => $sizes ) {
+			if ( ! isset( $this->known[ $url ] ) ) {
+				continue;
+			}
+			$base      = $type . ':' . $url;
+			$relation  = $this->known[ $url ];
+			$public_id = ! is_admin() ? $relation['public_id'] . '.' . $relation['format'] : null;
+			foreach ( $sizes as $size => $file_name ) {
+				$local_url = path_join( dirname( $base ), $file_name );
+				if ( isset( $cached[ $local_url ] ) ) {
+					$aliases[ $local_url ] = $cached[ $local_url ];
+					continue;
 				}
+				$aliases[ $local_url ] = $this->media->cloudinary_url( $relation['post_id'], explode( 'x', $size ), $relation['transformations'], $public_id );
 			}
 		}
+
 		// Move aliases to the end of the run, after images.
 		if ( ! empty( $aliases ) ) {
 			$replacements = array_merge( $replacements, $aliases );
@@ -1526,11 +1553,15 @@ public function prepare_delivery( $content ) {
 		$urls    = array_merge( $desized, $scaled );
 		$urls    = array_values( $urls ); // resets the index.
 
-		// clean out empty urls.
-		$cloudinary_urls = array_filter( $base_urls, array( $this->media, 'is_cloudinary_url' ) ); // clean out empty urls.
-		// Clean URLS for search.
-		$public_ids = array_filter( array_map( array( $this->media, 'get_public_id_from_url' ), $cloudinary_urls ) );
-
+		$public_ids = array();
+		// Lets only look for Cloudinary URLs on the frontend.
+		if ( ! is_admin() ) {
+			// clean out empty urls.
+			$cloudinary_urls = array_filter( $base_urls, array( $this->media, 'is_cloudinary_url' ) ); // clean out empty urls.
+			// Clean URLS for search.
+			$all_public_ids = array_filter( array_map( array( $this->media, 'get_public_id_from_url' ), $cloudinary_urls ) );
+			$public_ids     = array_unique( $all_public_ids );
+		}
 		if ( empty( $urls ) && empty( $public_ids ) ) {
 			return; // Bail since theres nothing.
 		}
@@ -1586,22 +1617,24 @@ public function query_relations( $public_ids, $urls = array() ) {
 	 * Catch attachment URLS from HTML content.
 	 *
 	 * @param string $content The HTML to catch URLS from.
+	 * @param string $context The content of the content.
 	 */
-	public function catch_urls( $content ) {
+	public function catch_urls( $content, $context = 'view' ) {
 
 		$this->init_delivery();
 		$this->prepare_delivery( $content );
-		$known = $this->convert_tags( $content );
 
+		if ( ! empty( $this->known ) ) {
+			$known = $this->convert_tags( $content, $context );
+			// Replace the knowns.
+			foreach ( $known as $src => $replace ) {
+				String_Replace::replace( $src, $replace );
+			}
+		}
 		// Attempt to get the unknowns.
 		if ( ! empty( $this->unknown ) ) {
 			$this->find_attachment_size_urls();
 		}
 
-		// Replace the knowns.
-		foreach ( $known as $src => $replace ) {
-			String_Replace::replace( $src, $replace );
-		}
-
 	}
 }
diff --git a/php/class-media.php b/php/class-media.php
index d20469dd9..58247abbb 100644
--- a/php/class-media.php
+++ b/php/class-media.php
@@ -1225,7 +1225,7 @@ protected function get_cache_key( $args ) {
 	 *
 	 * @param int          $attachment_id             The id of the attachment.
 	 * @param array|string $size                      The wp size to set for the URL.
-	 * @param array        $transformations           Set of transformations to apply to this url.
+	 * @param array|string $transformations           Set of transformations to apply to this url.
 	 * @param string|null  $cloudinary_id             Optional forced cloudinary ID.
 	 * @param bool         $overwrite_transformations Flag url is a breakpoint URL to stop re-applying default transformations.
 	 *
@@ -1260,6 +1260,9 @@ public function cloudinary_url( $attachment_id, $size = array(), $transformation
 			$set_size = $this->prepare_size( $attachment_id, $size );
 		}
 		// Prepare transformations.
+		if ( ! empty( $transformations ) && is_string( $transformations ) ) {
+			$transformations = $this->get_transformations_from_string( $transformations, $resource_type );
+		}
 		$pre_args['transformation'] = $this->get_transformations( $attachment_id, $transformations, $overwrite_transformations );
 
 		// Make a copy as not to destroy the options in \Cloudinary::cloudinary_url().
@@ -2772,6 +2775,8 @@ public function apply_media_library_filters( $query ) {
 
 				if ( ! empty( $result ) ) {
 					$query->set( 'post__in', $result );
+				} else {
+					$query->set( 'post__in', array( 0 ) );
 				}
 			}
 		}
@@ -2838,7 +2843,6 @@ public function setup() {
 			add_action( 'print_media_templates', array( $this, 'media_template' ) );
 			add_action( 'wp_enqueue_media', array( $this, 'editor_assets' ) );
 			add_action( 'wp_ajax_cloudinary-down-sync', array( $this, 'down_sync_asset' ) );
-			add_action( 'rest_api_init', array( $this, 'add_live_url_filters' ) );
 
 			// Filter to add cloudinary folder.
 			add_filter( 'upload_dir', array( $this, 'upload_dir' ) );
diff --git a/php/class-string-replace.php b/php/class-string-replace.php
index ad87c415c..64656bb26 100644
--- a/php/class-string-replace.php
+++ b/php/class-string-replace.php
@@ -8,6 +8,7 @@
 namespace Cloudinary;
 
 use Cloudinary\Component\Setup;
+use \Traversable;
 
 /**
  * String replace class.
@@ -21,6 +22,13 @@ class String_Replace implements Setup {
 	 */
 	public $plugin;
 
+	/**
+	 * Holds the context.
+	 *
+	 * @var string
+	 */
+	protected $context;
+
 	/**
 	 * Holds the list of strings and replacements.
 	 *
@@ -41,10 +49,38 @@ public function __construct( Plugin $plugin ) {
 	 * Setup the object.
 	 */
 	public function setup() {
-		add_action( 'the_content', array( $this, 'replace_strings' ), 1 );
-		add_action( 'template_redirect', array( $this, 'init' ), -1000 ); // Not crazy low, but low enough to catch most cases, but not too low that it may break AMP.
+		if ( is_admin() ) {
+			$this->admin_filters();
+		} else {
+			$this->public_filters();
+		}
+		$this->add_rest_filters();
+	}
+
+	/**
+	 * Add admin filters.
+	 */
+	protected function admin_filters() {
+		// Admin filters can call String_Replace frequently, which is fine, as performance is not an issue.
+		add_filter( 'media_send_to_editor', array( $this, 'replace_strings' ), 10, 2 );
+		add_filter( 'the_editor_content', array( $this, 'replace_strings' ), 10, 2 );
+		add_filter( 'wp_prepare_attachment_for_js', array( $this, 'replace_strings' ), 11 );
+		add_action( 'admin_init', array( $this, 'start_capture' ) );
+	}
+
+	/**
+	 * Add Public Filters.
+	 */
+	protected function public_filters() {
 		add_action( 'template_include', array( $this, 'init_debug' ), PHP_INT_MAX );
-		$types = get_post_types_by_support( 'editor' );
+		add_action( 'parse_request', array( $this, 'init' ), - 1000 ); // Not crazy low, but low enough to catch most cases, but not too low that it may break AMP.
+	}
+
+	/**
+	 * Add filters for REST API.
+	 */
+	protected function add_rest_filters() {
+		$types = get_post_types_by_support( 'author' );
 		foreach ( $types as $type ) {
 			$post_type = get_post_type_object( $type );
 			// Check if this is a rest supported type.
@@ -66,9 +102,9 @@ public function setup() {
 	 */
 	public function pre_filter_rest_content( $response, $post, $request ) {
 		$context = $request->get_param( 'context' );
-		if ( 'view' === $context ) {
-			$data                        = $response->get_data();
-			$data['content']['rendered'] = $this->replace_strings( $data['content']['rendered'] );
+		if ( 'view' === $context || 'edit' === $context ) {
+			$data = $response->get_data();
+			$data = $this->replace_strings( $data, $context );
 			$response->set_data( $data );
 		}
 
@@ -79,12 +115,20 @@ public function pre_filter_rest_content( $response, $post, $request ) {
 	 * Init the buffer capture and set the output callback.
 	 */
 	public function init() {
-		remove_action( 'the_content', array( $this, 'replace_strings' ), 1 ); // Remove the content filter.
 		if ( ! defined( 'CLD_DEBUG' ) || false === CLD_DEBUG ) {
-			ob_start( array( $this, 'replace_strings' ) );
+			$this->context = 'view';
+			$this->start_capture();
 		}
 	}
 
+	/**
+	 * Stop the buffer capture and set the output callback.
+	 */
+	public function start_capture() {
+		ob_start( array( $this, 'replace_strings' ) );
+		ob_start( array( $this, 'replace_strings' ) ); // Second call to catch early buffer flushing.
+	}
+
 	/**
 	 * Init the buffer capture in debug mode.
 	 *
@@ -94,6 +138,7 @@ public function init() {
 	 */
 	public function init_debug( $template ) {
 		if ( defined( 'CLD_DEBUG' ) && true === CLD_DEBUG && ! Utils::get_sanitized_text( '_bypass' ) ) {
+			$this->context = 'view';
 			ob_start();
 			include $template;
 			$html = ob_get_clean();
@@ -137,44 +182,114 @@ public static function replace( $search, $replace ) {
 	}
 
 	/**
-	 * Replace string in HTML.
+	 * Flatten an array into content.
 	 *
-	 * @param string $html The HTML.
+	 * @param array $content The array to flatten.
 	 *
 	 * @return string
 	 */
-	public function replace_strings( $html ) {
+	public function flatten( $content ) {
+		$flat = '';
+		if ( self::is_iterable( $content ) ) {
+			foreach ( $content as $item ) {
+				$flat .= "\r\n" . $this->flatten( $item );
+			}
+		} else {
+			$flat = $content;
+		}
+
+		return $flat;
+	}
+
+	/**
+	 * Check if the item is iterable.
+	 *
+	 * @param mixed $thing Thing to check.
+	 *
+	 * @return bool
+	 */
+	public static function is_iterable( $thing ) {
+
+		return is_array( $thing ) || is_object( $thing );
+	}
 
+	/**
+	 * Prime replacement strings.
+	 *
+	 * @param mixed  $content The content to prime replacements for.
+	 * @param string $context The context to use.
+	 */
+	protected function prime_replacements( $content, $context = 'view' ) {
+
+		if ( self::is_iterable( $content ) ) {
+			$content = $this->flatten( $content );
+		}
 		/**
 		 * Do replacement action.
 		 *
-		 * @hook cloudinary_string_replace
+		 * @hook  cloudinary_string_replace
+		 * @since 3.0.3 Added the `$context` argument.
 		 *
-		 * @param $html {string} The html of the page.
+		 * @param $content {string} The html of the page.
+		 * @param $context {string} The render context.
 		 */
-		do_action( 'cloudinary_string_replace', $html );
+		do_action( 'cloudinary_string_replace', $content, $context );
+	}
+
+	/**
+	 * Replace string in HTML.
+	 *
+	 * @param string|array $content The HTML.
+	 * @param string       $context The context to use.
+	 *
+	 * @return string
+	 */
+	public function replace_strings( $content, $context = 'view' ) {
+		static $last_content;
+		if ( empty( $content ) || $last_content === $content ) {
+			return $content; // Bail if nothing to replace.
+		}
+		// Captured a front end request, since the $context will be an int.
+		if ( ! empty( $this->context ) ) {
+			$context = $this->context;
+		}
+		if ( Utils::looks_like_json( $content ) ) {
+			$json_maybe = json_decode( $content, true );
+			if ( $json_maybe ) {
+				$content = $json_maybe;
+			}
+		}
+		$this->prime_replacements( $content, $context );
 		if ( ! empty( self::$replacements ) ) {
-			$html = self::do_replace( $html );
+			$content = self::do_replace( $content );
 		}
-
-		return $html;
+		self::reset();
+		$last_content = isset( $json_maybe ) ? wp_json_encode( $content ) : $content;
+		return $last_content;
 	}
 
 	/**
 	 * Do string replacements.
 	 *
-	 * @param string $content The content to do replacements on.
+	 * @param string|array $content The content to do replacements on.
 	 *
-	 * @return string
+	 * @return string|array
 	 */
 	public static function do_replace( $content ) {
-		return str_replace( array_keys( self::$replacements ), array_values( self::$replacements ), $content );
+
+		if ( self::is_iterable( $content ) ) {
+			foreach ( $content as &$item ) {
+				$item = self::do_replace( $item );
+			}
+		} else {
+			$content = str_replace( array_keys( self::$replacements ), array_values( self::$replacements ), $content );
+		}
+
+		return $content;
 	}
 
 	/**
 	 * Reset internal replacements.
-	 *
-	 * @return void
 	 */
 	public static function reset() {
 		self::$replacements = array();
diff --git a/php/class-utils.php b/php/class-utils.php
index 0384a9f78..33205dc3a 100644
--- a/php/class-utils.php
+++ b/php/class-utils.php
@@ -445,4 +445,15 @@ public static function pathinfo( $path, $flags = 15 ) {
 
 		return is_array( $pathinfo ) ? array_map( 'urldecode', $pathinfo ) : urldecode( $pathinfo );
 	}
+
+	/**
+	 * Check if a thing looks like a json string.
+	 *
+	 * @param mixed $thing The thing to check.
+	 *
+	 * @return bool
+	 */
+	public static function looks_like_json( $thing ) {
+		return is_string( $thing ) && in_array( ltrim( $thing )[0], array( '{', '[' ), true );
+	}
 }
diff --git a/php/media/class-filter.php b/php/media/class-filter.php
index 9d33cac8d..98303aae0 100644
--- a/php/media/class-filter.php
+++ b/php/media/class-filter.php
@@ -573,9 +573,6 @@ public function pre_filter_rest_content( $response, $post, $request ) {
 		$context = $request->get_param( 'context' );
 		if ( 'edit' === $context ) {
 			$data                   = $response->get_data();
-			$content                = $data['content']['raw'];
-			$data['content']['raw'] = $this->filter_out_local( $content );
-
 			// Handle meta if missing due to custom-fields not being supported.
 			if ( ! isset( $data['meta'] ) ) {
 				$data['meta'] = $request->get_param( 'meta' );
@@ -769,14 +766,6 @@ public function setup_hooks() {
 		add_filter( 'wp_insert_post_data', array( $this, 'prepare_amp_posts' ), 11 );
 		add_filter( 'wp_prepare_attachment_for_js', array( $this, 'filter_attachment_for_js' ), 11 );
 
-		// Add support for custom header.
-		add_filter( 'get_header_image_tag', array( $this, 'filter_out_local' ) );
-
-		// Add transformations.
-		add_filter( 'media_send_to_editor', array( $this, 'transform_to_editor' ), 10, 3 );
-
-		// Filter video codes.
-		add_filter( 'media_send_to_editor', array( $this, 'filter_video_embeds' ), 10, 3 );
 
 		// Enable Rest filters.
 		add_action( 'rest_api_init', array( $this, 'init_rest_filters' ) );
@@ -790,13 +779,6 @@ public function setup_hooks() {
 		// Filter to record current meta updating attachment.
 		add_filter( 'wp_update_attachment_metadata', array( $this, 'record_meta_update' ), 10, 2 );
 
-		// Filter out locals and responsive images setup.
-		if ( is_admin() ) {
-			// Filtering out locals.
-			add_filter( 'the_editor_content', array( $this, 'filter_out_local' ) );
-			add_filter( 'the_content', array( $this, 'filter_out_local' ), 100 );
-		}
-
 		// Add filter to match src when editing in block.
 		add_filter( 'wp_image_file_matches_image_meta', array( $this, 'edit_match_src' ), 10, 4 );
 	}
diff --git a/php/sync/class-sync-queue.php b/php/sync/class-sync-queue.php
index 07d290b9d..3ba013d53 100644
--- a/php/sync/class-sync-queue.php
+++ b/php/sync/class-sync-queue.php
@@ -320,9 +320,11 @@ protected function query_unsynced_data() {
 
 		$cached = get_transient( Sync::META_KEYS['dashboard_cache'] );
 		if ( empty( $cached ) ) {
+			$return                       = array();
 			$wpdb->cld_table              = Utils::get_relationship_table();
-			$return['total_assets']       = (int) $wpdb->get_var( "SELECT COUNT( DISTINCT post_id ) as total FROM {$wpdb->cld_table};" ); // phpcs:ignore WordPress.DB.DirectDatabaseQuery
-			$return['unoptimized_assets'] = (int) $wpdb->get_var( "SELECT COUNT( DISTINCT post_id ) as total FROM {$wpdb->cld_table} WHERE public_id IS NULL;" ); // phpcs:ignore WordPress.DB.DirectDatabaseQuery
+			$query_string                 = "SELECT COUNT( DISTINCT post_id ) as total FROM {$wpdb->cld_table} JOIN {$wpdb->posts} on( {$wpdb->cld_table}.post_id = {$wpdb->posts}.ID ) WHERE {$wpdb->posts}.post_type = 'attachment'";
+			$return['total_assets']       = (int) $wpdb->get_var( $query_string ); // phpcs:ignore WordPress.DB
+			$return['unoptimized_assets'] = (int) $wpdb->get_var( $query_string . ' AND public_id IS NULL' ); // phpcs:ignore WordPress.DB
 
 			$asset_sizes           = $wpdb->get_results( // phpcs:ignore WordPress.DB.DirectDatabaseQuery
 				$wpdb->prepare(