Fix issues with saving files in web app

Fix several web app UI details

css/general.css

@@ -284,6 +284,7 @@
 		height: 100%;
 		overflow-x: hidden;
 		overflow-y: auto;
+		flex-grow: 1;
 	}
 	.toolbar_wrapper > .toolbar.vertical {
 		width: 40px;

js/file_system.js

@@ -254,12 +254,15 @@ Object.assign(Blockbench, {
 			} else {
 
 				let a = document.createElement('a');
+				a.target = '_blank'
 
 				if (options.savetype === 'image') {
 					a.href = options.content;
 
 				} else if (options.savetype === 'zip' || options.savetype === 'buffer' || options.savetype === 'binary') {
-					let blob = new Blob(data, {type: "octet/stream"});
+					let blob = options.content instanceof Blob
+							 ? options.content
+							 : new Blob(options.content, {type: "octet/stream"});
 					a.href = window.URL.createObjectURL(blob);
 
 				} else {
@@ -269,7 +272,12 @@ Object.assign(Blockbench, {
 				a.download = file_name;
 				
 				if (Blockbench.browser === 'firefox') document.body.appendChild(a);
-				a.click();
+				var event = document.createEvent("MouseEvents");
+					event.initMouseEvent(
+							"click", true, false, window, 0, 0, 0, 0, 0
+							, false, false, false, false, 0, null
+					);
+				a.dispatchEvent(event);
 				if (Blockbench.browser === 'firefox') document.body.removeChild(a);
 
 			}

js/interface/dialog.js

@@ -478,8 +478,10 @@ window.Dialog = class Dialog {
 		if (this.width) {
 			jq_dialog.css('width', this.width+'px');
 		}
-		let first_focus = jq_dialog.find('.focusable_input').first();
-		if (first_focus) first_focus.focus();
+		if (!Blockbench.isTouch) {
+			let first_focus = jq_dialog.find('.focusable_input').first();
+			if (first_focus) first_focus.trigger('focus');
+		}
 
 		open_dialog = this.id;
 		open_interface = this;

js/plugin_loader.js

@@ -119,7 +119,6 @@ class Plugin {
 				})
 			});
 		});
-		return this;
 	}
 	async loadFromFile(file, first) {
 		var scope = this;

scripts/generate_pwa.js

@@ -6,7 +6,6 @@ workbox.generateSW({
 	globPatterns: [
 		'./index.html',
 		'./favicon.png',
-		'./service_worker.js',
 
 		'./js/**/*',
 		'./lib/**/*',