diff --git a/.vscode/extensions.json b/.vscode/extensions.json
index f0119e4a..bf08864f 100644
--- a/.vscode/extensions.json
+++ b/.vscode/extensions.json
@@ -1,7 +1,7 @@
 {
     "recommendations": [
         "bmewburn.vscode-intelephense-client",
-        "felixfbecker.php-debug",
+        "xdebug.php-debug",
         "shevaua.phpcs"
     ]
 }
diff --git a/app/controller/files.php b/app/controller/files.php
index 60b8bc64..8b8fe1cb 100644
--- a/app/controller/files.php
+++ b/app/controller/files.php
@@ -142,11 +142,20 @@ public function thumb($f3, $params)
             $c1 = imagecolorallocate($frame, 243, 243, 243);
             imagefilledrectangle($frame, $ox - $fb, $oy - $fb, $size - $ox + $fb, $size - $oy + $fb, $c1);
             $c2 = imagecolorallocate($frame, 230, 230, 230);
-            imagefilledpolygon($frame, array(
-                $size - $ox + $fb, $oy - $fb,
-                $size - $ox + $fb, $size - $oy + $fb,
-                $ox - $fb, $size - $oy + $fb,
-            ), 3, $c2);
+            // This is an incredibly stupid way of deprecating a parameter, thanks PHP.
+            if (PHP_VERSION_ID >= 80000) {
+                imagefilledpolygon($frame, array(
+                    $size - $ox + $fb, $oy - $fb,
+                    $size - $ox + $fb, $size - $oy + $fb,
+                    $ox - $fb, $size - $oy + $fb,
+                ), $c2);
+            } else {
+                imagefilledpolygon($frame, array(
+                    $size - $ox + $fb, $oy - $fb,
+                    $size - $ox + $fb, $size - $oy + $fb,
+                    $ox - $fb, $size - $oy + $fb,
+                ), 3, $c2);
+            }
         }
 
         // Copy thumbnail onto frame
diff --git a/app/helper/view.php b/app/helper/view.php
index 074bfebe..520b421a 100644
--- a/app/helper/view.php
+++ b/app/helper/view.php
@@ -22,6 +22,9 @@ public function __construct()
      */
     public function parseText($str, $options = array(), $ttl = null)
     {
+        if ($str === null || $str === '') {
+            return '';
+        }
         if ($options === null) {
             $options = array();
         }
@@ -238,6 +241,7 @@ protected function _parseEmoticons($str)
      */
     protected function _parseTextile($str, $escape = true)
     {
+        error_reporting(E_ALL ^ E_DEPRECATED); // Temporarily ignore deprecations because this lib is incompatible
         $tex = new \Netcarver\Textile\Parser('html5');
         $tex->setDimensionlessImages(true);
         $tex->setRestricted($escape);
@@ -286,7 +290,7 @@ public function gravatar($email, $size = 80)
         $f3 = \Base::instance();
         $rating = $f3->get("gravatar.rating") ? $f3->get("gravatar.rating") : "pg";
         $default = $f3->get("gravatar.default") ? $f3->get("gravatar.default") : "mm";
-        return "//gravatar.com/avatar/" . md5(strtolower($email)) .
+        return "https://gravatar.com/avatar/" . md5(strtolower($email ?? '')) .
                 "?s=" . intval($size) .
                 "&d=" . urlencode($default) .
                 "&r=" . urlencode($rating);
diff --git a/app/model/issue.php b/app/model/issue.php
index 1c0027a2..b6e6d5fe 100644
--- a/app/model/issue.php
+++ b/app/model/issue.php
@@ -10,20 +10,20 @@
  * @property int $type_id
  * @property string $name
  * @property string $description
- * @property int $parent_id
+ * @property ?int $parent_id
  * @property int $author_id
- * @property int $owner_id
+ * @property ?int $owner_id
  * @property int $priority
- * @property float $hours_total
- * @property float $hours_remaining
- * @property float $hours_spent
+ * @property ?float $hours_total
+ * @property ?float $hours_remaining
+ * @property ?float $hours_spent
  * @property string $created_date
- * @property string $closed_date
- * @property string $deleted_date
- * @property string $start_date
- * @property string $due_date
- * @property string $repeat_cycle
- * @property int $sprint_id
+ * @property ?string $closed_date
+ * @property ?string $deleted_date
+ * @property ?string $start_date
+ * @property ?string $due_date
+ * @property ?string $repeat_cycle
+ * @property ?int $sprint_id
  */
 class Issue extends \Model
 {
@@ -302,7 +302,7 @@ protected function _saveUpdate(bool $notify = true): Issue\Update
         $importantChanges = 0;
         $importantFields = array('status', 'name', 'description', 'owner_id', 'priority', 'due_date');
         foreach ($this->fields as $key => $field) {
-            if ($field["changed"] && rtrim($field["value"]) != rtrim($this->_getPrev($key))) {
+            if ($field["changed"] && rtrim($field["value"] ?? '') != rtrim($this->_getPrev($key) ?? '')) {
                 $updateField = new \Model\Issue\Update\Field();
                 $updateField->issue_update_id = $update->id;
                 $updateField->field = $key;
@@ -537,7 +537,11 @@ public function hashState(): array
     {
         $result = $this->cast();
         foreach ($result as &$value) {
-            $value = md5($value);
+            if ($value === null) {
+                $value = md5('');
+            } else {
+                $value = md5($value);
+            }
         }
         return $result;
     }
diff --git a/app/view/admin/config.html b/app/view/admin/config.html
index 97521ac1..7794f7b6 100644
--- a/app/view/admin/config.html
+++ b/app/view/admin/config.html
@@ -176,7 +176,7 @@
                         </div>
                         <div class="form-group">
                             <label class="control-label" for="imap-password">{{ @dict.password }}</label>
-                            <input type="text" class="form-control input-sm" name="imap-password" value="{{ str_repeat('*', strlen(@@imap.password)) }}">
+                            <input type="text" class="form-control input-sm" name="imap-password" value="{{ isset(@imap.password) ? str_repeat('*', strlen(@@imap.password)) : '' }}">
                         </div>
                         <div class="form-group">
                             <label class="control-label" for="mail-truncate_lines">{{ @dict.imap_truncate_lines }}</label>
diff --git a/app/view/blocks/dashboard-issue-list.html b/app/view/blocks/dashboard-issue-list.html
index 73155368..c7e1e656 100644
--- a/app/view/blocks/dashboard-issue-list.html
+++ b/app/view/blocks/dashboard-issue-list.html
@@ -18,7 +18,7 @@
                     <span class="label-{{ @item.priority < 0 ? 'default' : 'danger' }} priority" style="width: {{ !@item.priority ? 0 : 1 + 1 * abs(@item.priority) }}px;"></span>
                 </check>
             </p>
-            <check if="{{ strtotime(@item.due_date) }}">
+            <check if="{{ !empty(@item.due_date) && strtotime(@item.due_date) }}">
                 <p class="list-group-item-text">Due {{ date("l, F j", strtotime(@item.due_date)) }}</p>
             </check>
             <check if="{{ @item.sprint_id }}">
diff --git a/app/view/blocks/issue-list/issue.html b/app/view/blocks/issue-list/issue.html
index 8f523831..9546892b 100644
--- a/app/view/blocks/issue-list/issue.html
+++ b/app/view/blocks/issue-list/issue.html
@@ -25,7 +25,7 @@
         </false>
     </check>
     <td>{{ !empty(@item.sprint_start_date) ? date("n/j/y", strtotime(@item.sprint_start_date)) : "" }}</td>
-    <td>{{ ucwords(@@dict[@item.repeat_cycle]) ?: @dict.not_repeating }}</td>
+    <td>{{ isset(@dict[@item.repeat_cycle]) ? ucwords(@dict[@item.repeat_cycle]) : @dict.not_repeating }}</td>
     <td title="{{ date('Y-m-d H:i:s', @this->utc2local(@item.created_date)) }}">{{ date("n/j/y", @this->utc2local(@item.created_date)) }}</td>
     <td>{{ !empty(@item.due_date) ? date("n/j/y", strtotime(@item.due_date)) : "" }}</td>
     <check if="{{ !empty(@GET.status) && @GET.status != 'open' }}">
diff --git a/app/view/install.html b/app/view/install.html
index 075853bc..b6b2ce3c 100644
--- a/app/view/install.html
+++ b/app/view/install.html
@@ -86,7 +86,7 @@ <h4>Site Configuration</h4>
                                                 <label for="parser" class="col-sm-3 control-label">Text Parser</label>
                                                 <div class="col-sm-9">
                                                     <select class="form-control" name="parser" id="parser">
-                                                        <option value="markdown">Markdown (Recommended)</option>
+                                                        <option value="markdown" selected>Markdown (Recommended)</option>
                                                         <option value="textile">Textile (Deprecated)</option>
                                                         <option value="both">Markdown + Textile (Deprecated)</option>
                                                         <option value="">None</option>
diff --git a/app/view/issues/single.html b/app/view/issues/single.html
index 9e28c463..5d4ef747 100644
--- a/app/view/issues/single.html
+++ b/app/view/issues/single.html
@@ -177,7 +177,7 @@ <h3 class="pull-left issue-heading">
                     <dd>{{ @issue.hours_remaining ?: 0 }}</dd>
                 </check>
 
-                <check if="{{ strtotime(@issue.start_date) }}">
+                <check if="{{ @issue.start_date && strtotime(@issue.start_date) }}">
                     <dt>{{ @dict.cols.start_date }}</dt>
                     <dd>{{ date("D, M j, Y", strtotime(@issue.start_date)) }}</dd>
                 </check>
diff --git a/app/view/issues/single/dependencies.html b/app/view/issues/single/dependencies.html
index 3c245e42..b106ebd7 100644
--- a/app/view/issues/single/dependencies.html
+++ b/app/view/issues/single/dependencies.html
@@ -1,7 +1,7 @@
 <form id="dependency_form" class="form-horizontal">
     <input type="hidden" name="issue_id" value="{{ @issue.id }}">
     <div class="form-group">
-        <label class="col-md-4"><b>{{ @dict.task_depends }}</b></label>
+        <label class="col-md-5"><b>{{ @dict.task_depends }}</b></label>
         <div class="col-md-3">
             <input type="text" class="form-control input-sm" name="dependency_id" required>
         </div>
@@ -42,8 +42,8 @@
                         <td>{{ @item.dependency_type }}</td>
                         <td><a href="{{ @BASE }}/user/{{ @item.author_username }}">{{ @item.author_name | esc }}</a></td>
                         <td><a href="{{ @BASE }}/user/{{ @item.owner_username }}">{{ @item.owner_name | esc }}</a></td>
-                        <td data-sort-value="{{ strtotime(@item.start_date) }}" title="{{ date('M j, Y \\a\\t g:ia', strtotime(@item.start_date)) }}">{{ date("n/j/y", strtotime(@item.start_date)) }}</td>
-                        <td data-sort-value="{{ strtotime(@item.due_date) ?: 0 }}">{{ !empty(@item.due_date) ? date("n/j", strtotime(@item.due_date)) : "" }}</td>
+                        <td data-sort-value="{{ @item.start_date ? strtotime(@item.start_date) : 0 }}" title="{{ @item.start_date ? date('M j, Y \\a\\t g:ia', strtotime(@item.start_date)) : '' }}">{{ @item.start_date ? date("n/j/y", strtotime(@item.start_date)) : '' }}</td>
+                        <td data-sort-value="{{ @item.due_date ? strtotime(@item.due_date) : 0 }}">{{ !empty(@item.due_date) ? date("n/j", strtotime(@item.due_date)) : "" }}</td>
                         <td data-sort-value="{{ @item.status }}">{{ @item.status_name }}</td>
                         <td><a href="#" class="delete"><span class="fa fa-remove"></span></a></td>
                     </tr>
@@ -56,7 +56,7 @@
 <form id="dependent_form" class="form-horizontal">
     <input type="hidden" name="dependency_id" value="{{ @issue.id }}">
     <div class="form-group">
-        <label class="col-md-4"><strong>{{ @dict.task_dependency }}</strong></label>
+        <label class="col-md-5"><strong>{{ @dict.task_dependency }}</strong></label>
         <div class="col-md-3">
             <input type="text" class="form-control input-sm" name="issue_id" required>
         </div>
@@ -97,8 +97,8 @@
                         <td>{{ @item.dependency_type }}</td>
                         <td><a href="{{ @BASE }}/user/{{ @item.author_username }}">{{ @item.author_name | esc }}</a></td>
                         <td><a href="{{ @BASE }}/user/{{ @item.owner_username }}">{{ @item.owner_name | esc }}</a></td>
-                        <td data-sort-value="{{ strtotime(@item.start_date) }}" title="{{ date('M j, Y \\a\\t g:ia', strtotime(@item.start_date)) }}">{{ date("n/j/y", strtotime(@item.start_date)) }}</td>
-                        <td data-sort-value="{{ strtotime(@item.due_date) ?: 0 }}">{{ !empty(@item.due_date) ? date("n/j", strtotime(@item.due_date)) : "" }}</td>
+                        <td data-sort-value="{{ @item.start_date ? strtotime(@item.start_date) : 0 }}" title="{{ @item.start_date ? date('M j, Y \\a\\t g:ia', strtotime(@item.start_date)) : '' }}">{{ @item.start_date ? date("n/j/y", strtotime(@item.start_date)) : '' }}</td>
+                        <td data-sort-value="{{ @item.due_date ? strtotime(@item.due_date) : 0 }}">{{ !empty(@item.due_date) ? date("n/j", strtotime(@item.due_date)) : "" }}</td>
                         <td data-sort-value="{{ @item.status }}">{{ @item.status_name }}</td>
                         <td><a href="#" class="delete"><span class="fa fa-remove"></span></a></td>
                     </tr>
diff --git a/app/view/issues/single/related.html b/app/view/issues/single/related.html
index cc017690..980583b5 100644
--- a/app/view/issues/single/related.html
+++ b/app/view/issues/single/related.html
@@ -32,7 +32,7 @@
                             <td><a href="{{ @BASE }}/user/{{ @item.owner_username }}">{{ @item.owner_name | esc }}</a></td>
                             <td data-sort-value="{{ strtotime(@item.created_date) }}" title="{{ date('Y-m-d H:i:s', strtotime(@item.created_date)) }}">{{ date("n/j/y", strtotime(@item.created_date)) }}</td>
                             <td data-sort-value="{{ @item.priority }}">{{ @item.priority_name | esc }}</td>
-                            <td data-sort-value="{{ strtotime(@item.due_date) ?: 0 }}">{{ !empty(@item.due_date) ? date("n/j", strtotime(@item.due_date)) : "" }}</td>
+                            <td data-sort-value="{{ @item.due_date ? strtotime(@item.due_date) : 0 }}">{{ !empty(@item.due_date) ? date("n/j", strtotime(@item.due_date)) : "" }}</td>
                             <td data-sort-value="{{ @item.status }}">{{ @item.status_name | esc }}</td>
                         </tr>
                     </repeat>
diff --git a/app/view/user/single.html b/app/view/user/single.html
index 251e8f95..0d36a995 100644
--- a/app/view/user/single.html
+++ b/app/view/user/single.html
@@ -42,7 +42,9 @@ <h3>
                 <li class="active"><a href="#user-created" data-toggle="tab">{{ @dict.created_issues }}&ensp;<span class="badge">{{ @created_issues.total }}</span></a></li>
                 <li><a href="#user-assigned" data-toggle="tab">{{ @dict.assigned_issues }}&ensp;<span class="badge">{{ @assigned_issues.total }}</span></a></li>
                 <li><a href="#user-overdue" data-toggle="tab">{{ @dict.overdue_issues }}&ensp;<span class="badge">{{ @overdue_issues.total }}</span></a></li>
-                <li><a href="#user-tree" data-toggle="tab">{{ @dict.issue_tree }}</a></li>
+                <check if="{{ @this_user.role != 'group' }}">
+                    <li><a href="#user-tree" data-toggle="tab">{{ @dict.issue_tree }}</a></li>
+                </check>
             </ul>
             <div class="tab-content">
                 <div class="tab-pane fade in active" id="user-created">
@@ -53,13 +55,15 @@ <h3>
                     <set issues="{{ @assigned_issues }}" />
                     <include href="blocks/issue-list.html" />
                 </div>
-                <div class="tab-pane fade" id="user-tree">
-                    <p>{{ @dict.loading }}</p>
-                </div>
                 <div class="tab-pane fade" id="user-overdue">
                     <set issues="{{ @overdue_issues }}" />
                     <include href="blocks/issue-list.html" />
                 </div>
+                <check if="{{ @this_user.role != 'group' }}">
+                    <div class="tab-pane fade" id="user-tree">
+                        <p>{{ @dict.loading }}</p>
+                    </div>
+                </check>
             </div>
         </div>
 
diff --git a/composer.lock b/composer.lock
index daa4f410..9787654e 100644
--- a/composer.lock
+++ b/composer.lock
@@ -191,7 +191,7 @@
         },
         {
             "name": "symfony/polyfill-iconv",
-            "version": "v1.24.0",
+            "version": "v1.25.0",
             "source": {
                 "type": "git",
                 "url": "https://github.com/symfony/polyfill-iconv.git",
@@ -254,7 +254,7 @@
                 "shim"
             ],
             "support": {
-                "source": "https://github.com/symfony/polyfill-iconv/tree/v1.24.0"
+                "source": "https://github.com/symfony/polyfill-iconv/tree/v1.25.0"
             },
             "funding": [
                 {
@@ -274,7 +274,7 @@
         },
         {
             "name": "symfony/polyfill-intl-grapheme",
-            "version": "v1.24.0",
+            "version": "v1.25.0",
             "source": {
                 "type": "git",
                 "url": "https://github.com/symfony/polyfill-intl-grapheme.git",
@@ -335,7 +335,7 @@
                 "shim"
             ],
             "support": {
-                "source": "https://github.com/symfony/polyfill-intl-grapheme/tree/v1.24.0"
+                "source": "https://github.com/symfony/polyfill-intl-grapheme/tree/v1.25.0"
             },
             "funding": [
                 {
@@ -355,7 +355,7 @@
         },
         {
             "name": "symfony/polyfill-intl-normalizer",
-            "version": "v1.24.0",
+            "version": "v1.25.0",
             "source": {
                 "type": "git",
                 "url": "https://github.com/symfony/polyfill-intl-normalizer.git",
@@ -419,7 +419,7 @@
                 "shim"
             ],
             "support": {
-                "source": "https://github.com/symfony/polyfill-intl-normalizer/tree/v1.24.0"
+                "source": "https://github.com/symfony/polyfill-intl-normalizer/tree/v1.25.0"
             },
             "funding": [
                 {
@@ -439,7 +439,7 @@
         },
         {
             "name": "symfony/polyfill-mbstring",
-            "version": "v1.24.0",
+            "version": "v1.25.0",
             "source": {
                 "type": "git",
                 "url": "https://github.com/symfony/polyfill-mbstring.git",
@@ -502,7 +502,7 @@
                 "shim"
             ],
             "support": {
-                "source": "https://github.com/symfony/polyfill-mbstring/tree/v1.24.0"
+                "source": "https://github.com/symfony/polyfill-mbstring/tree/v1.25.0"
             },
             "funding": [
                 {
@@ -522,7 +522,7 @@
         },
         {
             "name": "symfony/polyfill-php72",
-            "version": "v1.24.0",
+            "version": "v1.25.0",
             "source": {
                 "type": "git",
                 "url": "https://github.com/symfony/polyfill-php72.git",
@@ -578,7 +578,7 @@
                 "shim"
             ],
             "support": {
-                "source": "https://github.com/symfony/polyfill-php72/tree/v1.24.0"
+                "source": "https://github.com/symfony/polyfill-php72/tree/v1.25.0"
             },
             "funding": [
                 {
@@ -598,16 +598,16 @@
         },
         {
             "name": "voku/anti-xss",
-            "version": "4.1.37",
+            "version": "4.1.39",
             "source": {
                 "type": "git",
                 "url": "https://github.com/voku/anti-xss.git",
-                "reference": "728e158427a263917f33b0a29eb75d866bd18d17"
+                "reference": "64a59ba4744e6722866ff3440d93561da9e85cd0"
             },
             "dist": {
                 "type": "zip",
-                "url": "https://api.github.com/repos/voku/anti-xss/zipball/728e158427a263917f33b0a29eb75d866bd18d17",
-                "reference": "728e158427a263917f33b0a29eb75d866bd18d17",
+                "url": "https://api.github.com/repos/voku/anti-xss/zipball/64a59ba4744e6722866ff3440d93561da9e85cd0",
+                "reference": "64a59ba4744e6722866ff3440d93561da9e85cd0",
                 "shasum": ""
             },
             "require": {
@@ -653,7 +653,7 @@
             ],
             "support": {
                 "issues": "https://github.com/voku/anti-xss/issues",
-                "source": "https://github.com/voku/anti-xss/tree/4.1.37"
+                "source": "https://github.com/voku/anti-xss/tree/4.1.39"
             },
             "funding": [
                 {
@@ -677,20 +677,20 @@
                     "type": "tidelift"
                 }
             ],
-            "time": "2022-02-15T01:57:51+00:00"
+            "time": "2022-03-08T17:03:58+00:00"
         },
         {
             "name": "voku/portable-ascii",
-            "version": "2.0.0",
+            "version": "2.0.1",
             "source": {
                 "type": "git",
                 "url": "https://github.com/voku/portable-ascii.git",
-                "reference": "9bd89e83cecdf8c37b64909454249eaed98b2c89"
+                "reference": "b56450eed252f6801410d810c8e1727224ae0743"
             },
             "dist": {
                 "type": "zip",
-                "url": "https://api.github.com/repos/voku/portable-ascii/zipball/9bd89e83cecdf8c37b64909454249eaed98b2c89",
-                "reference": "9bd89e83cecdf8c37b64909454249eaed98b2c89",
+                "url": "https://api.github.com/repos/voku/portable-ascii/zipball/b56450eed252f6801410d810c8e1727224ae0743",
+                "reference": "b56450eed252f6801410d810c8e1727224ae0743",
                 "shasum": ""
             },
             "require": {
@@ -727,7 +727,7 @@
             ],
             "support": {
                 "issues": "https://github.com/voku/portable-ascii/issues",
-                "source": "https://github.com/voku/portable-ascii/tree/2.0.0"
+                "source": "https://github.com/voku/portable-ascii/tree/2.0.1"
             },
             "funding": [
                 {
@@ -751,20 +751,20 @@
                     "type": "tidelift"
                 }
             ],
-            "time": "2022-01-24T18:59:03+00:00"
+            "time": "2022-03-08T17:03:00+00:00"
         },
         {
             "name": "voku/portable-utf8",
-            "version": "6.0.3",
+            "version": "6.0.4",
             "source": {
                 "type": "git",
                 "url": "https://github.com/voku/portable-utf8.git",
-                "reference": "82a714b5a4973974c1113e97b11c1044a8b8cb85"
+                "reference": "f6c78e492520115bb2d947c3a0d90a2c6b7a60a8"
             },
             "dist": {
                 "type": "zip",
-                "url": "https://api.github.com/repos/voku/portable-utf8/zipball/82a714b5a4973974c1113e97b11c1044a8b8cb85",
-                "reference": "82a714b5a4973974c1113e97b11c1044a8b8cb85",
+                "url": "https://api.github.com/repos/voku/portable-utf8/zipball/f6c78e492520115bb2d947c3a0d90a2c6b7a60a8",
+                "reference": "f6c78e492520115bb2d947c3a0d90a2c6b7a60a8",
                 "shasum": ""
             },
             "require": {
@@ -826,7 +826,7 @@
             ],
             "support": {
                 "issues": "https://github.com/voku/portable-utf8/issues",
-                "source": "https://github.com/voku/portable-utf8/tree/6.0.3"
+                "source": "https://github.com/voku/portable-utf8/tree/6.0.4"
             },
             "funding": [
                 {
@@ -850,7 +850,7 @@
                     "type": "tidelift"
                 }
             ],
-            "time": "2022-01-30T05:20:24+00:00"
+            "time": "2022-03-08T17:04:59+00:00"
         }
     ],
     "packages-dev": [