diff --git a/src/ui/ModalLayer.cpp b/src/ui/ModalLayer.cpp
index 59bffce..1c0feea 100644
--- a/src/ui/ModalLayer.cpp
+++ b/src/ui/ModalLayer.cpp
@@ -5,6 +5,7 @@
 #include <QEventLoop>
 #include <QFrame>
 #include <QMetaObject>
+#include <QMouseEvent>
 #include <QPainter>
 #include <QPoint>
 #include <QScrollArea>
@@ -133,6 +134,47 @@ void ModalLayer::paintEvent(QPaintEvent* /*event*/)
     painter.fillRect(rect(), m_dimColor);
 }
 
+void ModalLayer::mousePressEvent(QMouseEvent* event)
+{
+    m_pressedOutside = event->button() == Qt::LeftButton
+                       && isOutsideOpenModal(event->pos());
+
+    // Taken whether or not it dismisses anything: the window behind a modal receives no
+    // input, and closing the modal does not turn this click into one for what lies under
+    // it (REQ-UI-DIALOG-DISMISS).
+    event->accept();
+}
+
+void ModalLayer::mouseReleaseEvent(QMouseEvent* event)
+{
+    const bool pressedOutside = m_pressedOutside;
+    m_pressedOutside = false;
+    event->accept();
+
+    if (event->button() != Qt::LeftButton || !pressedOutside
+        || !isOutsideOpenModal(event->pos()) || m_stack.empty())
+    {
+        return;
+    }
+
+    // A drag that began inside the modal never gets here -- the widget it began on keeps
+    // the release -- so no gesture ends by discarding the modal it was made in.
+    ModalDialog* openModal = m_stack.back().content;
+    if (openModal->isDismissible())
+    {
+        openModal->requestDismiss();
+    }
+}
+
+bool ModalLayer::isOutsideOpenModal(const QPoint& position) const
+{
+    if (m_stack.empty())
+    {
+        return true;
+    }
+    return !m_stack.back().host->geometry().contains(position);
+}
+
 void ModalLayer::place(QScrollArea& host, ModalDialog& content,
                        const QRect& anchorRect) const
 {
diff --git a/src/ui/ModalLayer.h b/src/ui/ModalLayer.h
index f9c7e85..c9dd4b0 100644
--- a/src/ui/ModalLayer.h
+++ b/src/ui/ModalLayer.h
@@ -3,10 +3,12 @@
 #include <vector>
 
 #include <QColor>
+#include <QPoint>
 #include <QRect>
 #include <QWidget>
 
 class ModalDialog;
+class QMouseEvent;
 class QPaintEvent;
 class QScrollArea;
 
@@ -52,6 +54,8 @@ public:
 
 protected:
     void paintEvent(QPaintEvent* event) override;
+    void mousePressEvent(QMouseEvent* event) override;
+    void mouseReleaseEvent(QMouseEvent* event) override;
 
 private:
     // A modal and the scroll area it is shown in. The host is what the layer places and
@@ -69,7 +73,16 @@ private:
 
     void updateVisibility();
 
+    // Whether a point in this layer's coordinates lies beyond the open modal. A click on
+    // an inert part of the modal -- a label, the space between two controls -- arrives
+    // here too, propagated by the widget that ignored it, so where the click landed is
+    // what decides, never that the layer received it.
+    bool isOutsideOpenModal(const QPoint& position) const;
+
     QColor                   m_dimColor;
+    // Set by a left press that landed outside the open modal, so that only a press and a
+    // release both outside dismiss it (REQ-UI-DIALOG-DISMISS).
+    bool                     m_pressedOutside = false;
     std::vector<HostedModal> m_stack;  // bottom-most first; back() is the open one
     int                      m_holdCount = 0;
 };