Add custom minimum size for shader tabs

editor/plugins/shader_editor_plugin.cpp

@@ -833,6 +833,7 @@ ShaderEditorPlugin::ShaderEditorPlugin() {
 	left_panel->set_custom_minimum_size(Size2(100, 300) * EDSCALE);
 
 	shader_tabs = memnew(TabContainer);
+	shader_tabs->set_custom_minimum_size(Size2(460, 300) * EDSCALE);
 	shader_tabs->set_tabs_visible(false);
 	shader_tabs->set_h_size_flags(Control::SIZE_EXPAND_FILL);
 	main_split->add_child(shader_tabs);