Fix completer size

resources/qml/Completer.qml

@@ -100,7 +100,7 @@ Control {
 
         // Broken, see https://bugreports.qt.io/browse/QTBUG-102811
         //reuseItems: true
-        implicitWidth: listView.contentItem.childrenRect.width
+        implicitWidth: Math.max(listView.contentItem.childrenRect.width, 20)
         model: completer
         pixelAligned: true
         spacing: rowSpacing

src/timeline/TimelineViewManager.cpp

@@ -436,7 +436,7 @@ TimelineViewManager::focusMessageInput()
     emit focusInput();
 }
 
-QObject *
+QAbstractItemModel *
 TimelineViewManager::completerFor(const QString &completerName, const QString &roomId)
 {
     if (completerName == QLatin1String("user")) {

src/timeline/TimelineViewManager.h

@@ -134,8 +134,8 @@ public slots:
 
     void setVideoCallItem();
 
-    QObject *completerFor(const QString &completerName,
-                          const QString &roomId = QLatin1String(QLatin1String("")));
+    QAbstractItemModel *completerFor(const QString &completerName,
+                                     const QString &roomId = QLatin1String(QLatin1String("")));
     void forwardMessageToRoom(mtx::events::collections::TimelineEvents const *e, QString roomId);
 
     RoomlistModel *rooms() { return rooms_; }