diff --git a/public/js/upload_queue.js b/public/js/upload_queue.js
index a0953ff7..54384f62 100644
--- a/public/js/upload_queue.js
+++ b/public/js/upload_queue.js
@@ -1,215 +1,211 @@
-function UploadQueue(options) {
-	this.queue = options.queue_element;
-	this.preview_area = options.preview_area;
-	this.upload_progress = [];
-	this.upload_url = options.upload_url;
-	this.submit = options.submit_button;
-	this.addEvents();
-}
+class UploadQueue {
+	constructor(options) {
+		this.queue = options.queue_element;
+		this.preview_area = options.preview_area;
+		this.upload_progress = [];
+		this.upload_url = options.upload_url;
+		this.submit = options.submit_button;
+		this.addEvents();
+	}
 
-UploadQueue.prototype.addEvents = function() {
-	var that = this;
-	that.queue.addEventListener('change', function() {
-		that.showSpinner(that.queue, "Generating previews (not uploading yet!)");
-		that.clearPreviews();
-		for (var i = 0; i < that.queue.files.length; i++) {
-			var callback = (i !== that.queue.files.length - 1) ? null : function() {
-				that.hideSpinner();
-				that.submit.disabled = false;
+	addEvents() {
+		this.queue.addEventListener('change', event => {
+			this.showSpinner(this.queue, "Generating previews (not uploading yet!)");
+			this.clearPreviews();
+			for (let i = 0; i < this.queue.files.length; i++) {
+				const callback = (i !== this.queue.files.length - 1) ? null : () => {
+					this.hideSpinner();
+					this.submit.disabled = false;
+				};
+
+				if (this.queue.files[0].name.includes(".HEIC")) {
+					alert('Sorry, the HEIC image format is not supported.\nPlease convert your photos to JPEG before uploading.');
+					this.hideSpinner();
+					this.submit.disabled = false;
+					break;
+				}
+
+				this.addPreviewBoxForQueueSlot(i);
+				this.addPreviewForFile(this.queue.files[i], i, callback);
 			};
-
-			if (that.queue.files[0].name.includes(".HEIC")) {
-				alert('Sorry, the HEIC image format is not supported.\nPlease convert your photos to JPEG before uploading.');
-				that.hideSpinner();
-				that.submit.disabled = false;
-				break;
-			}
-
-			that.addPreviewBoxForQueueSlot(i);
-			that.addPreviewForFile(that.queue.files[i], i, callback);
-		};
-	});
-	that.submit.addEventListener('click', function(e) {
-		e.preventDefault();
-		that.process();
-	});
-	this.submit.disabled = true;
-};
-
-UploadQueue.prototype.clearPreviews = function() {
-	this.preview_area.innerHTML = '';
-	this.submit.disabled = true;
-	this.current_upload_index = -1;
-}
-
-UploadQueue.prototype.addPreviewBoxForQueueSlot = function(index) {
-	var preview_box = document.createElement('div');
-	preview_box.id = 'upload_preview_' + index;
-	this.preview_area.appendChild(preview_box);
-};
-
-UploadQueue.prototype.addPreviewForFile = function(file, index, callback) {
-	if (!file) {
-		return false;
-	}
-
-	var preview = document.createElement('canvas');
-	preview.title = file.name;
-
-	var preview_box = document.getElementById('upload_preview_' + index);
-	preview_box.appendChild(preview);
-
-	var reader = new FileReader();
-	var that = this;
-	reader.addEventListener('load', function() {
-		var original = document.createElement('img');
-		original.src = reader.result;
-
-		original.addEventListener('load', function() {
-			// Preparation: make canvas size proportional to the original image.
-			preview.height = 150;
-			preview.width = preview.height * (original.width / original.height);
-
-			// First pass: resize to 50% on temp canvas.
-			var temp = document.createElement('canvas'),
-				tempCtx = temp.getContext('2d');
-
-			temp.width = original.width * 0.5;
-			temp.height = original.height * 0.5;
-			tempCtx.drawImage(original, 0, 0, temp.width, temp.height);
-
-			// Second pass: resize again on temp canvas.
-			tempCtx.drawImage(temp, 0, 0, temp.width * 0.5, temp.height * 0.5);
-
-			// Final pass: resize to desired size on preview canvas.
-			var context = preview.getContext('2d');
-			context.drawImage(temp, 0, 0, temp.width * 0.5, temp.height * 0.5,
-				0, 0, preview.width, preview.height);
-
-			if (callback) {
-				callback();
-			}
 		});
-	}, false);
-	reader.readAsDataURL(file);
-};
-
-UploadQueue.prototype.process = function() {
-	this.showSpinner(this.submit, "Preparing to upload files...");
-	if (this.queue.files.length > 0) {
+		this.submit.addEventListener('click', event => {
+			event.preventDefault();
+			this.process();
+		});
 		this.submit.disabled = true;
-		this.nextFile();
 	}
-};
 
-UploadQueue.prototype.nextFile = function() {
-	var files = this.queue.files;
-	var i = ++this.current_upload_index;
-	if (i === files.length) {
-		this.hideSpinner();
-	} else {
-		this.setSpinnerLabel("Uploading file " + (i + 1) + " out of " + files.length);
-		this.sendFile(files[i], i, function() {
+	clearPreviews() {
+		this.preview_area.innerHTML = '';
+		this.submit.disabled = true;
+		this.current_upload_index = -1;
+	}
+
+	addPreviewBoxForQueueSlot(index) {
+		const preview_box = document.createElement('div');
+		preview_box.id = 'upload_preview_' + index;
+		this.preview_area.appendChild(preview_box);
+	}
+
+	addPreviewForFile(file, index, callback) {
+		if (!file) {
+			return false;
+		}
+
+		const preview = document.createElement('canvas');
+		preview.title = file.name;
+
+		const preview_box = document.getElementById('upload_preview_' + index);
+		preview_box.appendChild(preview);
+
+		const reader = new FileReader();
+		reader.addEventListener('load', event => {
+			const original = document.createElement('img');
+			original.src = reader.result;
+
+			original.addEventListener('load', function() {
+				// Preparation: make canvas size proportional to the original image.
+				preview.height = 150;
+				preview.width = preview.height * (original.width / original.height);
+
+				// First pass: resize to 50% on temp canvas.
+				const temp = document.createElement('canvas'),
+					tempCtx = temp.getContext('2d');
+
+				temp.width = original.width * 0.5;
+				temp.height = original.height * 0.5;
+				tempCtx.drawImage(original, 0, 0, temp.width, temp.height);
+
+				// Second pass: resize again on temp canvas.
+				tempCtx.drawImage(temp, 0, 0, temp.width * 0.5, temp.height * 0.5);
+
+				// Final pass: resize to desired size on preview canvas.
+				const context = preview.getContext('2d');
+				context.drawImage(temp, 0, 0, temp.width * 0.5, temp.height * 0.5,
+					0, 0, preview.width, preview.height);
+
+				if (callback) {
+					callback();
+				}
+			});
+		}, false);
+		reader.readAsDataURL(file);
+	}
+
+	process() {
+		this.showSpinner(this.submit, "Preparing to upload files...");
+		if (this.queue.files.length > 0) {
+			this.submit.disabled = true;
 			this.nextFile();
+		}
+	}
+
+	nextFile() {
+		const files = this.queue.files;
+		const i = ++this.current_upload_index;
+		if (i === files.length) {
+			this.hideSpinner();
+		} else {
+			this.setSpinnerLabel("Uploading file " + (i + 1) + " out of " + files.length);
+			this.sendFile(files[i], i, this.nextFile);
+		}
+	}
+
+	sendFile(file, index, callback) {
+		const request = new XMLHttpRequest();
+		request.addEventListener('error', event => {
+			this.updateProgress(index, -1);
 		});
-	}
-};
-
-UploadQueue.prototype.sendFile = function(file, index, callback) {
-	// Prepare the request.
-	var that = this;
-	var request = new XMLHttpRequest();
-	request.addEventListener('error', function(event) {
-		that.updateProgress(index, -1);
-	});
-	request.addEventListener('progress', function(event) {
-		that.updateProgress(index, event.loaded / event.total);
-	});
-	request.addEventListener('load', function(event) {
-		that.updateProgress(index, 1);
-		if (request.responseText !== null && request.status === 200) {
-			var obj = JSON.parse(request.responseText);
-			if (obj.error) {
-				alert(obj.error);
-				return;
+		request.addEventListener('progress', event => {
+			this.updateProgress(index, event.loaded / event.total);
+		});
+		request.addEventListener('load', event => {
+			this.updateProgress(index, 1);
+			if (request.responseText !== null && request.status === 200) {
+				const obj = JSON.parse(request.responseText);
+				if (obj.error) {
+					alert(obj.error);
+					return;
+				}
+				else if (callback) {
+					callback.call(this, obj);
+				}
 			}
-			else if (callback) {
-				callback.call(that, obj);
+		});
+
+		const data = new FormData();
+		data.append('uploads', file, file.name);
+
+		request.open('POST', this.upload_url, true);
+		request.send(data);
+	}
+
+	addProgressBar(index) {
+		if (index in this.upload_progress) {
+			return;
+		}
+
+		const progress_container = document.createElement('div');
+		progress_container.className = 'progress';
+
+		const progress = document.createElement('div');
+		progress_container.appendChild(progress);
+
+		const preview_box = document.getElementById('upload_preview_' + index);
+		preview_box.appendChild(progress_container);
+
+		this.upload_progress[index]	= progress;
+	}
+
+	updateProgress(index, progress) {
+		if (!(index in this.upload_progress)) {
+			this.addProgressBar(index);
+		}
+
+		const bar = this.upload_progress[index];
+
+		if (progress >= 0) {
+			bar.style.width = Math.ceil(progress * 100) + '%';
+		} else {
+			bar.style.width = "";
+			if (progress === -1) {
+				bar.className = "error";
 			}
 		}
-	});
-
-	var data = new FormData();
-	data.append('uploads', file, file.name);
-
-	request.open('POST', this.upload_url, true);
-	request.send(data);
-};
-
-UploadQueue.prototype.addProgressBar = function(index) {
-	if (index in this.upload_progress) {
-		return;
 	}
 
-	var progress_container = document.createElement('div');
-	progress_container.className = 'progress';
+	showSpinner(sibling, label) {
+		if (this.spinner) {
+			return;
+		}
 
-	var progress = document.createElement('div');
-	progress_container.appendChild(progress);
+		this.spinner = document.createElement('div');
+		this.spinner.className = 'spinner';
+		sibling.parentNode.appendChild(this.spinner);
 
-	var preview_box = document.getElementById('upload_preview_' + index);
-	preview_box.appendChild(progress_container);
-
-	this.upload_progress[index]	= progress;
-};
-
-UploadQueue.prototype.updateProgress = function(index, progress) {
-	if (!(index in this.upload_progress)) {
-		this.addProgressBar(index);
-	}
-
-	var bar = this.upload_progress[index];
-
-	if (progress >= 0) {
-		bar.style.width = Math.ceil(progress * 100) + '%';
-	} else {
-		bar.style.width = "";
-		if (progress === -1) {
-			bar.className = "error";
+		if (label) {
+			this.spinner_label = document.createElement('span');
+			this.spinner_label.className = 'spinner_label';
+			this.spinner_label.innerHTML = label;
+			sibling.parentNode.appendChild(this.spinner_label);
 		}
 	}
-};
 
-UploadQueue.prototype.showSpinner = function(sibling, label) {
-	if (this.spinner) {
-		return;
+	setSpinnerLabel(label) {
+		if (this.spinner_label) {
+			this.spinner_label.innerHTML = label;
+		}
 	}
 
-	this.spinner = document.createElement('div');
-	this.spinner.className = 'spinner';
-	sibling.parentNode.appendChild(this.spinner);
-
-	if (label) {
-		this.spinner_label = document.createElement('span');
-		this.spinner_label.className = 'spinner_label';
-		this.spinner_label.innerHTML = label;
-		sibling.parentNode.appendChild(this.spinner_label);
-	}
-};
-
-UploadQueue.prototype.setSpinnerLabel = function(label) {
-	if (this.spinner_label) {
-		this.spinner_label.innerHTML = label;
+	hideSpinner() {
+		if (this.spinner) {
+			this.spinner.parentNode.removeChild(this.spinner);
+			this.spinner = null;
+		}
+		if (this.spinner_label) {
+			this.spinner_label.parentNode.removeChild(this.spinner_label);
+			this.spinner_label = null;
+		}
 	}
 }
-
-UploadQueue.prototype.hideSpinner = function() {
-	if (this.spinner) {
-		this.spinner.parentNode.removeChild(this.spinner);
-		this.spinner = null;
-	}
-	if (this.spinner_label) {
-		this.spinner_label.parentNode.removeChild(this.spinner_label);
-		this.spinner_label = null;
-	}
-};