Add option to hide previews while tracking and autoscrolling

app/Resources/Tracker/bootstrap.js

@@ -133,6 +133,7 @@
 	STATE.onTrackingStateChanged(enabled => {
 		if (enabled) {
 			GUI.setStatus("Starting");
+			GUI.createTrackingStyles();
 			hasJustStarted = true;
 			
 			if (!starter()) {
@@ -142,6 +143,7 @@
 		}
 		else {
 			isSending = false;
+			GUI.deleteTrackingStyles();
 		}
 	});
 	

app/Resources/Tracker/scripts/dom.js

@@ -1,6 +1,8 @@
 class DOM {
 	/**
 	 * Returns a child element by its ID. Parent defaults to the entire document.
+	 * @param {string} id
+	 * @param {HTMLElement?} [parent]
 	 * @returns {HTMLElement}
 	 */
 	static id(id, parent) {
@@ -9,6 +11,9 @@ class DOM {
 	
 	/**
 	 * Returns the first child element containing the specified obfuscated class. Parent defaults to the entire document.
+	 * @param {string} cls
+	 * @param {HTMLElement?} [parent]
+	 * @returns {HTMLElement}
 	 */
 	static queryReactClass(cls, parent) {
 		return (parent || document).querySelector(`[class*="${cls}_"]`);

app/Resources/Tracker/scripts/gui.js

@@ -2,14 +2,17 @@
 const GUI = (function() {
 	let controller = null;
 	let settings = null;
+	let trackingStyles = null;
 	
 	const stateChangedEvent = () => {
 		if (settings) {
 			settings.ui.cbAutoscroll.checked = SETTINGS.autoscroll;
+			settings.ui.cbHidePreviewsWhileAutoscrolling.checked = SETTINGS.hidePreviewsWhileAutoscrolling;
 			settings.ui.optsAfterFirstMsg[SETTINGS.afterFirstMsg].checked = true;
 			settings.ui.optsAfterSavedMsg[SETTINGS.afterSavedMsg].checked = true;
 			
 			const autoscrollDisabled = !SETTINGS.autoscroll;
+			settings.ui.cbHidePreviewsWhileAutoscrolling.disabled = autoscrollDisabled;
 			Object.values(settings.ui.optsAfterFirstMsg).forEach(ele => ele.disabled = autoscrollDisabled);
 			Object.values(settings.ui.optsAfterSavedMsg).forEach(ele => ele.disabled = autoscrollDisabled);
 		}
@@ -54,6 +57,7 @@ const GUI = (function() {
 			
 			controller.ui.btnClose.addEventListener("click", () => {
 				this.hideController();
+				this.deleteTrackingStyles();
 				window.DHT_ON_UNLOAD.forEach(f => f());
 				delete window.DHT_ON_UNLOAD;
 				delete window.DHT_LOADED;
@@ -84,6 +88,7 @@ const GUI = (function() {
 			const radio = (type, id, label) => "<label><input id='dht-cfg-" + type + "-" + id + "' name='dht-" + type + "' type='radio'> " + label + "</label><br>";
 			const html = `
 <label><input id='dht-cfg-autoscroll' type='checkbox'> Autoscroll</label><br>
+<label><input id='dht-cfg-hide-previews-while-autoscrolling' type='checkbox'> Hide previews to improve browser performance</label><br>
 <br>
 <label>After reaching the first message in channel...</label><br>
 ${radio("afm", "nothing", "Continue Tracking")}
@@ -93,8 +98,7 @@ ${radio("afm", "switch", "Switch to Next Channel")}
 <label>After reaching a previously saved message...</label><br>
 ${radio("asm", "nothing", "Continue Tracking")}
 ${radio("asm", "pause", "Pause Tracking")}
-${radio("asm", "switch", "Switch to Next Channel")}
-<p id='dht-cfg-note'>It is recommended to disable link and image previews to avoid putting unnecessary strain on your browser.</p>`;
+${radio("asm", "switch", "Switch to Next Channel")}`;
 			
 			settings = {
 				styles: DOM.createStyle(`/*[CSS-SETTINGS]*/`),
@@ -107,9 +111,10 @@ ${radio("asm", "switch", "Switch to Next Channel")}
 			});
 			
 			settings.ui = {
-				cbAutoscroll: DOM.id("dht-cfg-autoscroll"),
-				optsAfterFirstMsg: {},
-				optsAfterSavedMsg: {}
+				/** @type {HTMLInputElement} */ cbAutoscroll: DOM.id("dht-cfg-autoscroll"),
+				/** @type {HTMLInputElement} */ cbHidePreviewsWhileAutoscrolling: DOM.id("dht-cfg-hide-previews-while-autoscrolling"),
+				/** @type {Object.<number, HTMLInputElement>} */ optsAfterFirstMsg: {},
+				/** @type {Object.<number, HTMLInputElement>} */ optsAfterSavedMsg: {}
 			};
 			
 			settings.ui.optsAfterFirstMsg[CONSTANTS.AUTOSCROLL_ACTION_NOTHING] = DOM.id("dht-cfg-afm-nothing");
@@ -124,6 +129,10 @@ ${radio("asm", "switch", "Switch to Next Channel")}
 				SETTINGS.autoscroll = settings.ui.cbAutoscroll.checked;
 			});
 			
+			settings.ui.cbHidePreviewsWhileAutoscrolling.addEventListener("change", () => {
+				SETTINGS.hidePreviewsWhileAutoscrolling = settings.ui.cbHidePreviewsWhileAutoscrolling.checked;
+			});
+			
 			Object.keys(settings.ui.optsAfterFirstMsg).forEach(key => {
 				settings.ui.optsAfterFirstMsg[key].addEventListener("click", () => {
 					SETTINGS.afterFirstMsg = key;
@@ -152,6 +161,29 @@ ${radio("asm", "switch", "Switch to Next Channel")}
 			if (controller) {
 				controller.ui.textStatus.innerText = state;
 			}
+		},
+		
+		createTrackingStyles() {
+			if (trackingStyles) {
+				return;
+			}
+			
+			let style = "";
+			
+			if (SETTINGS.autoscroll && SETTINGS.hidePreviewsWhileAutoscrolling) {
+				style += `div[id^="message-accessories-"] { display: none; }`;
+			}
+			
+			if (style.length > 0) {
+				trackingStyles = DOM.createStyle(style);
+			}
+		},
+		
+		deleteTrackingStyles() {
+			if (trackingStyles) {
+				DOM.removeElement(trackingStyles);
+				trackingStyles = null;
+			}
 		}
 	};
 })();

app/Resources/Tracker/scripts/settings.js

@@ -35,17 +35,28 @@ const SETTINGS = (function() {
 		obj[name] = value;
 	};
 	
+	const defaults = {
+		"_autoscroll": true,
+		"_hidePreviewsWhileAutoscrolling": true,
+		"_afterFirstMsg": CONSTANTS.AUTOSCROLL_ACTION_PAUSE,
+		"_afterSavedMsg": CONSTANTS.AUTOSCROLL_ACTION_PAUSE,
+	};
+	
 	let loaded = DOM.loadFromCookie("DHT_SETTINGS");
+	let hasChanged = false;
 	
 	if (!loaded) {
-		loaded = {
-			"_autoscroll": true,
-			"_afterFirstMsg": CONSTANTS.AUTOSCROLL_ACTION_PAUSE,
-			"_afterSavedMsg": CONSTANTS.AUTOSCROLL_ACTION_PAUSE
-		};
-		
+		loaded = defaults;
 		IS_FIRST_RUN = true;
 	}
+	else {
+		for (const property in defaults) {
+			if (!(property in loaded)) {
+				loaded[property] = defaults[property];
+				hasChanged = true;
+			}
+		}
+	}
 	
 	const root = {
 		onSettingsChanged(callback) {
@@ -54,10 +65,11 @@ const SETTINGS = (function() {
 	};
 	
 	defineTriggeringProperty(root, "autoscroll", loaded._autoscroll);
+	defineTriggeringProperty(root, "hidePreviewsWhileAutoscrolling", loaded._hidePreviewsWhileAutoscrolling);
 	defineTriggeringProperty(root, "afterFirstMsg", loaded._afterFirstMsg);
 	defineTriggeringProperty(root, "afterSavedMsg", loaded._afterSavedMsg);
 	
-	if (IS_FIRST_RUN) {
+	if (IS_FIRST_RUN || hasChanged) {
 		saveSettings();
 	}
 	

app/Resources/Tracker/styles/settings.css

@@ -18,11 +18,13 @@
   height: 262px;
   margin-left: -400px;
   margin-top: -131px;
+  line-height: 120%;
   padding: 8px;
   background-color: #fff;
   z-index: 1000002;
 }
 
-#dht-cfg-note {
-  margin-top: 22px;
+#dht-cfg label {
+  display: inline-block;
+  margin: 1px 0;
 }