diff --git a/kcmkwin/kwindecoration/kcm.cpp b/kcmkwin/kwindecoration/kcm.cpp
--- a/kcmkwin/kwindecoration/kcm.cpp
+++ b/kcmkwin/kwindecoration/kcm.cpp
@@ -83,6 +83,8 @@
 {
     m_proxyModel->setSourceModel(m_model);
     m_proxyModel->setFilterCaseSensitivity(Qt::CaseInsensitive);
+    m_proxyModel->setSortCaseSensitivity(Qt::CaseInsensitive);
+    m_proxyModel->sort(0);
     connect(m_ui->filter, &QLineEdit::textChanged, m_proxyModel, &QSortFilterProxyModel::setFilterFixedString);
 
     m_quickView = new QQuickView(0);