diff --git a/README.md b/README.md
index 2239b2c..14cc5c0 100644
--- a/README.md
+++ b/README.md
@@ -4,6 +4,10 @@ This is a browser based software for creating pixel art
 
 The tool can be viewed online here: https://lospec.com/pixel-editor
 
+## How to contribute
+
+Please do not submit pull requests with new features or core changes. Instead, please file an issue first for discussion.
+
 ## What to Contribute
 
 Any changes that fix bugs or add features are welcome.
@@ -15,10 +19,9 @@ Suggestions / Planned features:
 - Documentation
 
 - Possibility to hide and resize menus (layers, palette)
-- Line tool
 - Tiled mode
 - Load palette from LPE file
-- Symmetry options
+- Symmetry options (currently being worked on)
 
 - Mobile
     - Touch equivalent for mouse clicks
diff --git a/css/_canvas.scss b/css/_canvas.scss
index 40633fb..5d02f4c 100644
--- a/css/_canvas.scss
+++ b/css/_canvas.scss
@@ -69,6 +69,8 @@
 }
 
 #brush-preview {
+	background-color:black;
+	opacity:0.3;
 	position: absolute;
 	border: solid 1px #fff;
 	z-index: 1200;
diff --git a/js/ColorModule.js b/js/ColorModule.js
index f2ce578..b4170fe 100644
--- a/js/ColorModule.js
+++ b/js/ColorModule.js
@@ -98,8 +98,7 @@ const ColorModule = (() => {
         //left clicked color
         if (e.which == 1) {
             // remove current color selection
-            var selectedColor = document.querySelector('#colors-menu li.selected');
-            if (selectedColor) selectedColor.classList.remove('selected');
+            document.querySelector('#colors-menu li.selected')?.classList.remove('selected');
     
             //set current color
             updateCurrentColor(e.target.style.backgroundColor);
@@ -125,7 +124,7 @@ const ColorModule = (() => {
         const newColor = new Color("hsv", Math.floor(Math.random()*360), Math.floor(Math.random()*100), Math.floor(Math.random()*100)).hex;
 
         //remove current color selection
-        document.querySelector('#colors-menu li.selected').classList.remove('selected');
+        document.querySelector('#colors-menu li.selected')?.classList.remove('selected');
 
         //add new color and make it selected
         let addedColor = addColor(newColor);
@@ -369,8 +368,7 @@ const ColorModule = (() => {
             if (newColRgb.r + newColRgb.g + newColRgb.b < darkestColorRgb.r + darkestColorRgb.g + darkestColorRgb.b) {
 
                 //remove current color selection
-                var selectedColor = document.querySelector('#colors-menu li.selected');
-                if (selectedColor) selectedColor.classList.remove('selected');
+                document.querySelector('#colors-menu li.selected')?.classList.remove('selected');
 
                 //set as current color
                 newColorElement.classList.add('selected');
diff --git a/js/Events.js b/js/Events.js
index 299cca0..e3504ab 100644
--- a/js/Events.js
+++ b/js/Events.js
@@ -1,4 +1,6 @@
 class Events {
+    customCallback = {};
+
     /** Used to programmatically create an input event
      * 
      * @param {*} keyCode KeyCode of the key to press
@@ -89,6 +91,13 @@ class Events {
         return element;
     }
     
+    /** Register a callback for a certain window event
+     * 
+     * @param {*} event The event to register to
+     * @param {*} elementId The id of the element that will listen to the event
+     * @param {*} functionCallback The function to callback when the event is shoot 
+     * @param  {...any} args Arguments for the callback
+     */
     static on(event, elementId, functionCallback, ...args) {
         //if element provided is string, get the actual element
         const element = Util.getElement(elementId);
@@ -99,6 +108,14 @@ class Events {
         });
     }
 
+    /** Register a callback for a certain window event that is shot by the children of 
+     *  an element passed as an argument
+     * 
+     * @param {*} event The event to register to
+     * @param {*} elementId The id of the element whose children will listen to the event
+     * @param {*} functionCallback The function to callback when the event is shoot 
+     * @param  {...any} args Arguments for the callback
+     */
     static onChildren(event, parentElement, functionCallback, ...args) {
         parentElement = Util.getElement(parentElement);
         const children = parentElement.children;
@@ -108,4 +125,27 @@ class Events {
             on(event, children[i], functionCallback, ...args);
         }
     }
+
+    /** Registers a callback for a custom (non HTML) event
+     * 
+     * @param {*} event The event to register to
+     * @param {*} functionCallback The function to call
+     */
+    static onCustom(event, functionCallback) {
+        if (customCallback[event] === undefined)
+            customCallback[event] = [];
+        
+        customCallback[event].push(functionCallback);
+    }
+
+    /** Emits a custom (non HTML) event
+     * 
+     * @param {*} event The event to emit
+     * @param  {...any} args The arguments for that event
+     */
+    static emit(event, ...args) {
+        if (customCallback[event] != undefined) 
+            for (let i=0; i<customCallback[event].length; i++)
+                customCallback[event][i](args);
+    }
 }
\ No newline at end of file
diff --git a/js/FileManager.js b/js/FileManager.js
index a655304..e0cb000 100644
--- a/js/FileManager.js
+++ b/js/FileManager.js
@@ -180,6 +180,9 @@ const FileManager = (() => {
         reader.onload = function (e) {
             let dictionary = JSON.parse(e.target.result);
             Startup.newPixel(dictionary['canvasWidth'], dictionary['canvasHeight'], dictionary);
+            for (let i=0; i<dictionary['color' + i] != null; i++) {
+                ColorModule.addColor(dictionary['color'+i]);
+            }
         }
     }
 
diff --git a/js/Layer.js b/js/Layer.js
index d78f8e2..3d01a37 100644
--- a/js/Layer.js
+++ b/js/Layer.js
@@ -23,7 +23,7 @@ class Layer {
         this.canvasSize = [width, height];
         // REFACTOR: the canvas should actually be a Canvas instance
         this.canvas = Util.getElement(canvas);
-        // REFACOTR: the context could be an attribute of the canvas class, but it's a bit easier
+        // REFACTOR: the context could be an attribute of the canvas class, but it's a bit easier
         // to just type layer.context, we should discuss this
         this.context = this.canvas.getContext('2d');
         this.isSelected = false;
diff --git a/js/Settings.js b/js/Settings.js
index 8c16843..f93c8ae 100644
--- a/js/Settings.js
+++ b/js/Settings.js
@@ -1,5 +1,3 @@
-// REFACTOR: convert to IIFE
-
 const Settings = (() => {
     let settings;
     let settingsFromCookie;
diff --git a/js/ToolManager.js b/js/ToolManager.js
new file mode 100644
index 0000000..c28e2e8
--- /dev/null
+++ b/js/ToolManager.js
@@ -0,0 +1,14 @@
+const ToolManager = (() => {
+    /** What it should do
+     * 
+     * - Listen to mouse events
+     *      - Bind mouse events
+     *      - Call tool functions
+     * 
+     *  
+     */
+
+    return {
+
+    }
+})
\ No newline at end of file
diff --git a/js/_mouseEvents.js b/js/_mouseEvents.js
index 963d17f..f11636b 100644
--- a/js/_mouseEvents.js
+++ b/js/_mouseEvents.js
@@ -100,8 +100,7 @@ window.addEventListener("mouseup", function (mouseEvent) {
 	      //if picked color matches this color
 	      if (newColor == colors[i].jscolor.toString()) {
 	        //remove current color selection
-	        let selectedColor = document.querySelector("#colors-menu li.selected")
-	        if (selectedColor) selectedColor.classList.remove("selected");
+	        document.querySelector("#colors-menu li.selected")?.classList.remove("selected");
 
 	      	//set current color
 
diff --git a/js/_tools.js b/js/_tools.js
index 15b6fa6..1bef501 100644
--- a/js/_tools.js
+++ b/js/_tools.js
@@ -4,6 +4,51 @@ var tool = {};
 
 //class for tools
 class Tool {
+	name = "AbstractTool";
+	
+	cursorType = {};
+	cursorHTMLElement = undefined;
+	currBrushSize = 1;
+	prevBrushSize = 1;
+
+	startMousePos = {};
+	prevMousePos = {};
+	endMousePos = {};
+
+	onSelect() {
+
+	}
+
+	onHover(cursorPosition) {
+		let toSub = 1;
+        // Prevents the brush to be put in the middle of pixels
+        if (this.currentBrushSize % 2 == 0) {
+            toSub = 0.5;
+        }        
+        brushPreview.style.left = (Math.floor(cursorLocation[0] / zoom) * zoom + currentLayer.canvas.offsetLeft - this.currentBrushSize * zoom / 2 - zoom / 2 + toSub * zoom) + 'px';
+        brushPreview.style.top = (Math.floor(cursorLocation[1] / zoom) * zoom + currentLayer.canvas.offsetTop - this.currentBrushSize * zoom / 2 - zoom / 2 + toSub * zoom) + 'px';
+	}
+
+	onDeselect() {
+
+	}
+
+	onStart() {
+
+	}
+
+	onDrag() {
+
+	}
+
+	onEnd() {
+
+	}
+
+	updateCursor2() {
+
+	}
+
 	constructor (name, options) {
 
 		//stores the name in object, only needed for legacy functions from when currentTool was just a string
@@ -102,4 +147,20 @@ class Tool {
 }
 
 
-/*global dragging currentTool, currentToolTemp, selectionCanceled, endSelection*/
\ No newline at end of file
+/*global dragging currentTool, currentToolTemp, selectionCanceled, endSelection*/
+
+/**
+ * Class selectionTool extends Tool {
+ * 		imageDataToMove
+ * 		startDataPos
+ * 		currDataPos
+ * 		finalDataPos
+ * 		canMove
+ * 		
+ * 		movePreview()
+ * 		
+ * 		// start and end selection just overwrite the onStart and onEnd methods
+ * 
+ * }
+ * 
+ */
\ No newline at end of file