diff --git a/qubesmanager/qube_manager.py b/qubesmanager/qube_manager.py
index 711bc3639..462a3bb7a 100644
--- a/qubesmanager/qube_manager.py
+++ b/qubesmanager/qube_manager.py
@@ -198,7 +198,8 @@ def helpEvent(self, event, view, option, index):
                 QToolTip.showText(event.globalPos(),
                     self.tr(
                         "The qube is prohibited from starting\n"
-                        "See `qvm-features` manual for more information"
+                        "Prohibition rationale is available in qube settings "
+                        "-> Advanced tab"
                     ),
                     view
                 )
@@ -721,7 +722,7 @@ def filterAcceptsRow(self, sourceRow, sourceParent):
             return super().filterAcceptsRow(sourceRow, sourceParent)
 
         if self.window.show_running.isChecked() and \
-                vm.state['power'] != 'Halted':
+                not vm.state['power'] in ['Halted', 'Blocked']:
             return super().filterAcceptsRow(sourceRow, sourceParent)
         if self.window.show_halted.isChecked() and \
                 vm.state['power'] == 'Halted':
diff --git a/qubesmanager/settings.py b/qubesmanager/settings.py
index e0f08a954..d7defae60 100644
--- a/qubesmanager/settings.py
+++ b/qubesmanager/settings.py
@@ -1020,6 +1020,18 @@ def __init_advanced_tab__(self):
             self.run_in_debug_mode.setVisible(False)
             self.run_in_debug_mode.setEnabled(False)
 
+        rationale = utils.get_feature(self.vm, "prohibit-start", "")
+        if rationale:
+            self.prohibit_start_rationale.setText(rationale)
+        self.prohibit_start_rationale.setVisible(bool(rationale))
+        self.prohibit_start_rationale.textEdited.connect(
+            self.prohibit_start_rationale_edited
+        )
+        self.prohibit_start_checkbox.setChecked(bool(rationale))
+        self.prohibit_start_checkbox.clicked.connect(
+            self.prohibit_start_checked
+        )
+
         utils.initialize_widget(
             widget=self.allow_fullscreen,
             choices=[
@@ -1041,6 +1053,16 @@ def __init_advanced_tab__(self):
                                                      'gui-allow-utf8-titles'))
         self.allow_utf8_initial = self.allow_utf8.currentIndex()
 
+    def prohibit_start_checked(self, status):
+        self.prohibit_start_rationale.setVisible(bool(status))
+        self.prohibit_start_rationale.setFocus()
+
+    def prohibit_start_rationale_edited(self, text):
+        self.prohibit_start_checkbox.setChecked(bool(text))
+        self.prohibit_start_rationale.setStyleSheet(
+            "" if bool(text) else "#prohibit_start_rationale { color: red;}"
+        )
+
     def enable_seamless(self):
         try:
             self.vm.run_service_for_stdio("qubes.SetGuiMode", input=b'SEAMLESS')
@@ -1146,6 +1168,17 @@ def __apply_advanced_tab__(self):
         except qubesadmin.exc.QubesException as ex:
             msg.append(str(ex))
 
+        rationale = self.vm.features.get("prohibit-start", "")
+        if (self.prohibit_start_checkbox.isChecked() != bool(rationale)) or (
+            bool(rationale)
+            and self.prohibit_start_rationale.text() != rationale
+        ):
+            rationale = self.prohibit_start_rationale.text()
+            if bool(rationale) and self.prohibit_start_checkbox.isChecked():
+                self.vm.features["prohibit-start"] = rationale
+            else:
+                del self.vm.features["prohibit-start"]
+
         if self.allow_fullscreen_initial !=\
                 self.allow_fullscreen.currentIndex():
             try:
diff --git a/qubesmanager/tests/test_vm_settings.py b/qubesmanager/tests/test_vm_settings.py
index 9cae6a3b3..9619847fd 100644
--- a/qubesmanager/tests/test_vm_settings.py
+++ b/qubesmanager/tests/test_vm_settings.py
@@ -1028,6 +1028,41 @@ def test_215_bootmode_appvm_nondefault(settings_fixture):
         "Boot mode not changed"
 
 
+@check_errors
+@pytest.mark.parametrize("settings_fixture", TEST_VMS, indirect=True)
+def test_213_prohibit_start(settings_fixture):
+    settings_window, page, vm_name = settings_fixture
+    vm = settings_window.qubesapp.domains[vm_name]
+
+    r = vm.features.get("prohibit-start", "")
+    assert settings_window.prohibit_start_checkbox.isChecked() == bool(r)
+    if r:
+        assert settings_window.prohibit_start_rationale.text() == r
+
+    settings_window.prohibit_start_checkbox.setChecked(not bool(r))
+
+    if bool(r):
+        settings_window.prohibit_start_rationale.setText("")
+        expected_call = (
+            vm.name,
+            "admin.vm.feature.Remove",
+            "prohibit-start",
+            None,
+        )
+    else:
+        settings_window.prohibit_start_rationale.setText("RATIONALE")
+        expected_call = (
+            vm.name,
+            "admin.vm.feature.Set",
+            "prohibit-start",
+            "RATIONALE".encode(),
+        )
+
+    assert expected_call not in settings_window.qubesapp.actual_calls
+    settings_window.qubesapp.expected_calls[expected_call] = b"0\x00"
+    settings_window.accept()
+
+
 # FIREWALL TAB
 
 @check_errors
diff --git a/ui/settingsdlg.ui b/ui/settingsdlg.ui
index 85dfd7946..84b455dd1 100644
--- a/ui/settingsdlg.ui
+++ b/ui/settingsdlg.ui
@@ -742,14 +742,35 @@ border-width: 1px;</string>
               <property name="topMargin">
                <number>15</number>
               </property>
-              <item row="2" column="0">
+              <item row="2" column="0" colspan="2">
+               <layout class="QHBoxLayout" name="horizontalLayout_prohibit_start">
+                <item>
+                 <widget class="QCheckBox" name="prohibit_start_checkbox">
+                  <property name="text">
+                   <string>Prohibit start</string>
+                  </property>
+                 </widget>
+                </item>
+                <item>
+                 <widget class="QLineEdit" name="prohibit_start_rationale">
+                  <property name="text">
+                   <string>Rationale for start prohibition...</string>
+                  </property>
+                  <property name="placeholderText">
+                   <string>Start prohibition rationale is mandatory!</string>
+                  </property>
+                 </widget>
+                </item>
+               </layout>
+              </item>
+              <item row="3" column="0">
                <widget class="QCheckBox" name="provides_network_checkbox">
                 <property name="text">
                  <string>Provides network</string>
                 </property>
                </widget>
               </item>
-              <item row="3" column="0">
+              <item row="4" column="0">
                <widget class="QCheckBox" name="dvm_template_checkbox">
                 <property name="toolTip">
                  <string>&lt;html&gt;&lt;head/&gt;&lt;body&gt;&lt;p&gt;Allows using this qube as a template for disposables. Disposables will inherit the qube's state (configuration, installed programs, etc.), but their state will not persist between restarts. &lt;/p&gt;&lt;p&gt;Setting this option will cause this qube to be listed as an option in the &amp;quot;Default disposable template&amp;quot; list for all other qubes.&lt;/p&gt;&lt;p&gt;Only AppVMs and StandaloneVMs could be turned in to Disposable Templates&lt;/p&gt;&lt;/body&gt;&lt;/html&gt;</string>