Replace deprecated QLayout::setMargin by QLayout::setContentsMargin. * libgui/src/documentation-bookmarks.cc (documentation_bookmarks::documentation_bookmarks), libgui/src/documentation.cc (documentation::documentation), libgui/src/files-dock-widget.cc (files_dock_widget::files_dock_widget), libgui/src/history-dock-widget.cc (history_dock_widget::construct), libgui/src/m-editor/file-editor-tab.cc (file_editor_tab::file_editor_tab), libgui/src/m-editor/file-editor.cc (file_editor::construct), libgui/src/m-editor/find-dialog.cc (find_dialog::find_dialog), libgui/src/workspace-view.cc (workspace_view::workspace_view): Replace deprecated function QLayout::setMargin by QLayout::setContentsMargins with four equal arguments.

--- a/libgui/src/history-dock-widget.cc	Sun Apr 09 23:05:40 2023 -0400
+++ b/libgui/src/history-dock-widget.cc	Tue Apr 11 21:30:34 2023 +0200
@@ -312,14 +312,14 @@
   filter_layout->addWidget (filter_label);
   filter_layout->addWidget (m_filter_checkbox);
   filter_layout->addWidget (m_filter);
-  filter_layout->setMargin(0);
+  filter_layout->setContentsMargins (0, 0, 0, 0);
   m_filter_widget->setLayout (filter_layout);
 
   QVBoxLayout *hist_layout = new QVBoxLayout ();
   hist_layout->addWidget (m_filter_widget);
   hist_layout->addWidget (m_history_list_view);
 
-  hist_layout->setMargin (2);
+  hist_layout->setContentsMargins (2, 2, 2, 2);
   hist_layout->setSpacing (0);
   widget ()->setLayout (hist_layout);