Resolves tdf#137408 - Bad positioning of first items in extension dialog

Change-Id: Ic54ac8377bbfbd2c5b5b995ef8615bf0961bd100
Reviewed-on: https://gerrit.libreoffice.org/c/core/+/104051
Reviewed-by: Heiko Tietze <heiko.tietze@documentfoundation.org>
Tested-by: Heiko Tietze <heiko.tietze@documentfoundation.org>
diff --git a/cui/source/dialogs/AdditionsDialog.cxx b/cui/source/dialogs/AdditionsDialog.cxx
index 7eb277b..7d5d953 100644
--- a/cui/source/dialogs/AdditionsDialog.cxx
+++ b/cui/source/dialogs/AdditionsDialog.cxx
@@ -631,7 +631,7 @@ AdditionsItem::AdditionsItem(weld::Widget* pParent, AdditionsDialog* pParentDial

    // AdditionsItem set location
    m_xContainer->set_grid_left_attach(0);
    m_xContainer->set_grid_top_attach(pParentDialog->m_aAdditionsItems.size() - 1);
    m_xContainer->set_grid_top_attach(pParentDialog->m_aAdditionsItems.size());

    // Set maximum length of the extension title
    OUString sExtensionName;