Put WebUI security related options into a groupbox

src/gui/optionsdialog.ui

@@ -3154,6 +3154,12 @@ Specify an IPv4 or IPv6 address. You can specify "0.0.0.0" for any IPv
                  </layout>
                 </widget>
                </item>
+               <item>
+                <widget class="QGroupBox" name="groupBox_3">
+                 <property name="title">
+                  <string>Security</string>
+                 </property>
+                 <layout class="QVBoxLayout" name="verticalLayout_33">
                   <item>
                    <widget class="QCheckBox" name="checkClickjacking">
                     <property name="text">
@@ -3202,6 +3208,9 @@ Use ';' to split multiple entries. Can use wildcard '*'.</string>
                     </layout>
                    </widget>
                   </item>
+                 </layout>
+                </widget>
+               </item>
                <item>
                 <widget class="QGroupBox" name="checkDynDNS">
                  <property name="title">

src/webui/www/private/preferences_content.html

@@ -411,7 +411,6 @@
         <legend>QBT_TR(Web User Interface (Remote control))QBT_TR[CONTEXT=OptionsDialog]</legend>
         <label class="leftLabelMedium" for="webui_address_value">QBT_TR(IP address:)QBT_TR[CONTEXT=OptionsDialog]</label><input type="text" id="webui_address_value" />
         <label for="webui_port_value" style="margin-left: 10px;">QBT_TR(Port:)QBT_TR[CONTEXT=OptionsDialog]</label><input type="text" id="webui_port_value" style="width: 4em;" /><br/>
-        <label class="leftLabelMedium" for="webui_domain_textarea">QBT_TR(Server domains:)QBT_TR[CONTEXT=OptionsDialog]</label><textarea id="webui_domain_textarea" rows="1" cols="70"></textarea><br/>
         <input type="checkbox" id="webui_upnp_checkbox" />
         <label for="webui_upnp_checkbox">QBT_TR(Use UPnP / NAT-PMP to forward the port from my router)QBT_TR[CONTEXT=OptionsDialog]</label><br/>
         <fieldset class="settings">
@@ -449,6 +448,8 @@
             </div>
         </fieldset>
 
+        <fieldset class="settings">
+            <legend>QBT_TR(Security)QBT_TR[CONTEXT=OptionsDialog]</legend>
             <div class="formRow">
                 <input type="checkbox" id="clickjacking_protection_checkbox" />
                 <label for="clickjacking_protection_checkbox">QBT_TR(Enable clickjacking protection)QBT_TR[CONTEXT=OptionsDialog]</label>
@@ -457,11 +458,19 @@
                 <input type="checkbox" id="csrf_protection_checkbox" />
                 <label for="csrf_protection_checkbox">QBT_TR(Enable Cross-Site Request Forgery (CSRF) protection)QBT_TR[CONTEXT=OptionsDialog]</label>
             </div>
-        <div class="formRow">
+
-            <input type="checkbox" id="host_header_validation_checkbox" />
+            <fieldset class="settings">
+                <legend>
+                    <input type="checkbox" id="host_header_validation_checkbox" onclick="updateHostHeaderValidationSettings();" />
                     <label for="host_header_validation_checkbox">QBT_TR(Enable Host header validation)QBT_TR[CONTEXT=OptionsDialog]</label>
+                </legend>
+                <div class="formRow">
+                    <label class="leftLabelMedium" for="webui_domain_textarea">QBT_TR(Server domains:)QBT_TR[CONTEXT=OptionsDialog]</label>
+                    <textarea id="webui_domain_textarea" rows="1" cols="60"></textarea>
                 </div>
             </fieldset>
+        </fieldset>
+    </fieldset>
 
     <fieldset class="settings">
         <legend><input type="checkbox" id="use_dyndns_checkbox" onclick="updateDynDnsSettings();" />