diff --git a/uidev/src/testbed/testbed_any.rs b/uidev/src/testbed/testbed_any.rs
index a5ac9c9..6bea26f 100644
--- a/uidev/src/testbed/testbed_any.rs
+++ b/uidev/src/testbed/testbed_any.rs
@@ -1,7 +1,10 @@
 use crate::{assets, testbed::Testbed};
 use glam::Vec2;
 use wgui::{
-    event::EventListenerCollection, globals::WguiGlobals, layout::Layout, parser::ParserState,
+    event::EventListenerCollection,
+    globals::WguiGlobals,
+    layout::Layout,
+    parser::{ParseDocumentParams, ParserState},
 };
 
 pub struct TestbedAny {
@@ -20,8 +23,14 @@ impl TestbedAny {
 
         let globals = WguiGlobals::new(Box::new(assets::Asset {}))?;
 
-        let (layout, state) =
-            wgui::parser::new_layout_from_assets(globals, listeners, &path, false)?;
+        let (layout, state) = wgui::parser::new_layout_from_assets(
+            listeners,
+            &ParseDocumentParams {
+                globals,
+                path: &path,
+                extra: Default::default(),
+            },
+        )?;
         Ok(Self { layout, state })
     }
 }
diff --git a/uidev/src/testbed/testbed_generic.rs b/uidev/src/testbed/testbed_generic.rs
index 44d5dfa..cd2d338 100644
--- a/uidev/src/testbed/testbed_generic.rs
+++ b/uidev/src/testbed/testbed_generic.rs
@@ -12,7 +12,7 @@ use wgui::{
     globals::WguiGlobals,
     i18n::Translation,
     layout::{Layout, Widget},
-    parser::ParserState,
+    parser::{ParseDocumentParams, ParserState},
     widget::label::WidgetLabel,
 };
 
@@ -58,8 +58,14 @@ impl TestbedGeneric {
 
         let globals = WguiGlobals::new(Box::new(assets::Asset {}))?;
 
-        let (layout, state) =
-            wgui::parser::new_layout_from_assets(globals, listeners, XML_PATH, false)?;
+        let (layout, state) = wgui::parser::new_layout_from_assets(
+            listeners,
+            &ParseDocumentParams {
+                globals,
+                path: XML_PATH,
+                extra: Default::default(),
+            },
+        )?;
 
         let label_cur_option = state.fetch_widget(&layout.state, "label_current_option")?;
 
diff --git a/wgui/src/parser/mod.rs b/wgui/src/parser/mod.rs
index 4e907b4..bb368ee 100644
--- a/wgui/src/parser/mod.rs
+++ b/wgui/src/parser/mod.rs
@@ -105,12 +105,12 @@ impl ParserState {
 
 	pub fn process_template<U1, U2>(
 		&mut self,
+		doc_params: &ParseDocumentParams,
 		template_name: &str,
 		layout: &mut Layout,
 		listeners: &mut EventListenerCollection<U1, U2>,
 		widget_id: WidgetID,
 		template_parameters: HashMap<Rc<str>, Rc<str>>,
-		dev_mode: bool,
 	) -> anyhow::Result<()> {
 		let Some(template) = self.templates.get(template_name) else {
 			anyhow::bail!("no template named \"{}\" found", template_name);
@@ -125,7 +125,7 @@ impl ParserState {
 			components: self.components.clone(),       // FIXME: prevent copying
 			components_id_map: self.components_id_map.clone(), // FIXME: prevent copying
 			templates: Default::default(),
-			dev_mode,
+			doc_params,
 		};
 
 		let file = ParserFile {
@@ -157,6 +157,7 @@ struct MacroAttribs {
 }
 
 struct ParserContext<'a, U1, U2> {
+	doc_params: &'a ParseDocumentParams<'a>,
 	layout: &'a mut Layout,
 	listeners: &'a mut EventListenerCollection<U1, U2>,
 	var_map: HashMap<Rc<str>, Rc<str>>,
@@ -165,7 +166,6 @@ struct ParserContext<'a, U1, U2> {
 	templates: HashMap<Rc<str>, Rc<Template>>,
 	components: Vec<Component>,
 	components_id_map: HashMap<Rc<str>, ComponentWeak>,
-	dev_mode: bool,
 }
 
 // Parses a color from a HTML hex string
@@ -641,12 +641,12 @@ fn parse_children<'a, U1, U2>(
 	for child_node in node.children() {
 		match node.attribute("ignore_in_mode") {
 			Some("dev") => {
-				if !ctx.dev_mode {
+				if !ctx.doc_params.extra.dev_mode {
 					continue;
 				}
 			}
 			Some("live") => {
-				if ctx.dev_mode {
+				if ctx.doc_params.extra.dev_mode {
 					continue;
 				}
 			}
@@ -689,11 +689,12 @@ fn parse_children<'a, U1, U2>(
 }
 
 fn create_default_context<'a, U1, U2>(
+	doc_params: &'a ParseDocumentParams,
 	layout: &'a mut Layout,
 	listeners: &'a mut EventListenerCollection<U1, U2>,
-	dev_mode: bool,
 ) -> ParserContext<'a, U1, U2> {
 	ParserContext {
+		doc_params,
 		layout,
 		listeners,
 		ids: Default::default(),
@@ -702,20 +703,33 @@ fn create_default_context<'a, U1, U2>(
 		macro_attribs: Default::default(),
 		components: Default::default(),
 		components_id_map: Default::default(),
-		dev_mode,
 	}
 }
 
+pub struct UnusedAttribInfo {}
+
+#[derive(Default)]
+pub struct ParseDocumentExtra {
+	//pub on_unused_attrib: Option<Box<dyn Fn(UnusedAttribInfo)>>,
+	pub dev_mode: bool,
+}
+
+// filled-in by you in `new_layout_from_assets` function
+pub struct ParseDocumentParams<'a> {
+	pub globals: WguiGlobals,      // mandatory field
+	pub path: &'a str,             // mandatory field
+	pub extra: ParseDocumentExtra, // optional field, can be Default-ed
+}
+
 pub fn parse_from_assets<U1, U2>(
+	doc_params: &ParseDocumentParams,
 	layout: &mut Layout,
 	listeners: &mut EventListenerCollection<U1, U2>,
 	parent_id: WidgetID,
-	path: &str,
-	dev_mode: bool,
 ) -> anyhow::Result<ParserState> {
-	let path = PathBuf::from(path);
+	let path = PathBuf::from(doc_params.path);
 
-	let mut ctx = create_default_context(layout, listeners, dev_mode);
+	let mut ctx = create_default_context(doc_params, layout, listeners);
 
 	let (file, node_layout) = get_doc_from_path(&mut ctx, &path)?;
 	parse_document_root(file, &mut ctx, parent_id, node_layout)?;
@@ -737,14 +751,12 @@ pub fn parse_from_assets<U1, U2>(
 }
 
 pub fn new_layout_from_assets<U1, U2>(
-	globals: WguiGlobals,
 	listeners: &mut EventListenerCollection<U1, U2>,
-	path: &str,
-	dev_mode: bool,
+	doc_params: &ParseDocumentParams,
 ) -> anyhow::Result<(Layout, ParserState)> {
-	let mut layout = Layout::new(globals)?;
+	let mut layout = Layout::new(doc_params.globals.clone())?;
 	let widget = layout.root_widget;
-	let state = parse_from_assets(&mut layout, listeners, widget, path, dev_mode)?;
+	let state = parse_from_assets(doc_params, &mut layout, listeners, widget)?;
 	Ok((layout, state))
 }
 
diff --git a/wlx-overlay-s/src/gui/panel.rs b/wlx-overlay-s/src/gui/panel.rs
index 7e86c95..86a0269 100644
--- a/wlx-overlay-s/src/gui/panel.rs
+++ b/wlx-overlay-s/src/gui/panel.rs
@@ -44,10 +44,12 @@ impl<S> GuiPanel<S> {
         let mut listeners = EventListenerCollection::<AppState, S>::default();
 
         let (layout, parser_state) = wgui::parser::new_layout_from_assets(
-            app.wgui_globals.clone(),
             &mut listeners,
-            path,
-            false,
+            &wgui::parser::ParseDocumentParams {
+                globals: app.wgui_globals.clone(),
+                path,
+                extra: Default::default(),
+            },
         )?;
 
         let context = WguiContext::new(&mut app.wgui_shared, 1.0)?;
diff --git a/wlx-overlay-s/src/overlays/keyboard/builder.rs b/wlx-overlay-s/src/overlays/keyboard/builder.rs
index a0ebdd3..0ecf976 100644
--- a/wlx-overlay-s/src/overlays/keyboard/builder.rs
+++ b/wlx-overlay-s/src/overlays/keyboard/builder.rs
@@ -75,12 +75,14 @@ where
         keymap = None;
     }
 
-    let (_, mut gui_state_key) = wgui::parser::new_layout_from_assets(
-        app.wgui_globals.clone(),
-        &mut panel.listeners,
-        "gui/keyboard.xml",
-        false,
-    )?;
+    let parse_doc_params = wgui::parser::ParseDocumentParams {
+        globals: app.wgui_globals.clone(),
+        path: "gui/keyboard.xml",
+        extra: Default::default(),
+    };
+
+    let (_, mut gui_state_key) =
+        wgui::parser::new_layout_from_assets(&mut panel.listeners, &parse_doc_params)?;
 
     for row in 0..layout.key_sizes.len() {
         let (div, _) = panel.layout.add_child(
@@ -159,12 +161,12 @@ where
 
             let template_key = format!("Key{:?}", key.cap_type);
             gui_state_key.process_template(
+                &parse_doc_params,
                 &template_key,
                 &mut panel.layout,
                 &mut panel.listeners,
                 div,
                 params,
-                false,
             )?;
 
             if let Some(widget_id) = gui_state_key.ids.get(&*my_id) {