First attempt.

imports/Spectral/Component/Timeline/TimelineContainer.qml

@@ -0,0 +1,23 @@
+import QtQuick 2.12
+import QtQuick.Controls 2.12 as Controls
+import QtQuick.Layouts 1.12
+
+import org.kde.kirigami 2.4 as Kirigami
+
+Controls.Control {
+    default property alias innerObject : column.children
+
+    horizontalPadding: Kirigami.Units.largeSpacing
+    verticalPadding: Kirigami.Units.smallSpacing
+
+    contentItem: Column {
+        id: column
+
+        SectionDelegate {
+            anchors.horizontalCenter: parent.horizontalCenter
+            width: Math.min(implicitWidth, parent.width)
+
+            visible: showSection
+        }
+    }
+}