crash the window when the building is wrong

gui/scripts/windowman.JS

@@ -3,6 +3,9 @@ Window and window content management */
 
 import texts from "./read.js";
 
+// MAKE SURE TO TURN THIS OFF DURING BUILD.
+let DEBUG = false;
+
 class windowman {
 	static new(URL, height, width) {
 		this.window = chrome.windows.create({
@@ -16,10 +19,11 @@ class windowman {
 	// Prepare the window with its metadata.
 	constructor() {
 		function headers() {
+		let LOAD_STATE = true;
 			let UI = {
-        library: [
+				"CSS": [
 					chrome.runtime.getURL(
-            "gui/styles/external/mdi/materialdesignicons.min.css",
+						"gui/styles/external/fonts/materialdesignicons.min.css",
 					),
 					chrome.runtime.getURL(
 						"gui/styles/external/materialize/css/materialize.css",
@@ -28,13 +32,35 @@ class windowman {
 				],
 			};
 
-      UI.library.forEach((source) => {
+
+			for (let index = 0; index < UI[`CSS`].length; index++) {
+				const source = UI.CSS[index];
+				
+				(async () => {
+					const net = await import(chrome.runtime.getURL(`/scripts/net.js`));
+			
+					let resource = false;
+					try {
+						resource = await net.download(source, `text`, true);
+					} catch(err) {};
+	
+					if (resource) {
 						let metadata_element = document.createElement(`link`);
 						metadata_element.setAttribute(`rel`, `stylesheet`);
 						metadata_element.setAttribute(`type`, `text/css`);
 						metadata_element.setAttribute(`href`, source);
 						document.querySelector(`head`).appendChild(metadata_element);
-      });
+					} else {
+						const alerts = (await import(chrome.runtime.getURL(`/gui/scripts/alerts.js`))).default;
+						const reader = (await import(chrome.runtime.getURL(`/gui/scripts/read.js`))).default;
+	
+						alerts.error(-1, reader.localized(`error_msg_fileNotFound`), true, [source]);
+
+						// Stop loading the page when an error has occured; it's not going to work! 
+						if (!DEBUG) {window.close()};
+					}
+				})();
+			}
 		}
 
 		// Get the window.