diff --git a/Cargo.lock b/Cargo.lock
index 8839b7c..d9a92db 100644
--- a/Cargo.lock
+++ b/Cargo.lock
@@ -68,6 +68,17 @@ version = "1.0.70"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 checksum = "7de8ce5e0f9f8d88245311066a578d72b7af3e7088f32783804676302df237e4"
 
+[[package]]
+name = "async-recursion"
+version = "1.0.4"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "0e97ce7de6cf12de5d7226c73f5ba9811622f4db3a5b91b55c53e987e5f91cba"
+dependencies = [
+ "proc-macro2",
+ "quote",
+ "syn 2.0.13",
+]
+
 [[package]]
 name = "async-trait"
 version = "0.1.68"
@@ -240,6 +251,7 @@ name = "cove"
 version = "0.6.1"
 dependencies = [
  "anyhow",
+ "async-recursion",
  "async-trait",
  "clap",
  "cookie",
diff --git a/Cargo.toml b/Cargo.toml
index 63742b3..ef096ec 100644
--- a/Cargo.toml
+++ b/Cargo.toml
@@ -5,6 +5,7 @@ edition = "2021"
 
 [dependencies]
 anyhow = "1.0.70"
+async-recursion = "1.0.4"
 async-trait = "0.1.68"
 clap = { version = "4.2.1", features = ["derive", "deprecated"] }
 cookie = "0.17.0"
diff --git a/src/ui/chat.rs b/src/ui/chat.rs
index 475f7f0..f9f0367 100644
--- a/src/ui/chat.rs
+++ b/src/ui/chat.rs
@@ -11,7 +11,7 @@ use std::{fmt, io};
 use async_trait::async_trait;
 use parking_lot::FairMutex;
 use time::OffsetDateTime;
-use toss::{Frame, Size, Styled, Terminal};
+use toss::{Frame, Size, Styled, Terminal, WidthDb};
 
 use crate::store::{Msg, MsgStore};
 
@@ -139,14 +139,19 @@ pub enum Chat<M: Msg, S: MsgStore<M>> {
 #[async_trait]
 impl<M, S> Widget for Chat<M, S>
 where
-    M: Msg + ChatMsg,
+    M: Msg + ChatMsg + Send + Sync,
     M::Id: Send + Sync,
     S: MsgStore<M> + Send + Sync,
     S::Error: fmt::Display,
 {
-    fn size(&self, frame: &mut Frame, max_width: Option<u16>, max_height: Option<u16>) -> Size {
+    async fn size(
+        &self,
+        widthdb: &mut WidthDb,
+        max_width: Option<u16>,
+        max_height: Option<u16>,
+    ) -> Size {
         match self {
-            Self::Tree(tree) => tree.size(frame, max_width, max_height),
+            Self::Tree(tree) => tree.size(widthdb, max_width, max_height).await,
         }
     }
 
diff --git a/src/ui/chat/blocks.rs b/src/ui/chat/blocks.rs
index 240981c..bb596cb 100644
--- a/src/ui/chat/blocks.rs
+++ b/src/ui/chat/blocks.rs
@@ -20,11 +20,12 @@ pub struct Block<I> {
 }
 
 impl<I> Block<I> {
-    pub fn new<W: Into<BoxedWidget>>(frame: &mut Frame, id: I, widget: W) -> Self {
+    pub async fn new<W: Into<BoxedWidget>>(frame: &mut Frame, id: I, widget: W) -> Self {
         // Interestingly, rust-analyzer fails to deduce the type of `widget`
         // here but rustc knows it's a `BoxedWidget`.
         let widget = widget.into();
-        let size = widget.size(frame, Some(frame.size().width), None);
+        let max_width = frame.size().width;
+        let size = widget.size(frame.widthdb(), Some(max_width), None).await;
         let height = size.height.into();
         Self {
             id,
diff --git a/src/ui/chat/tree.rs b/src/ui/chat/tree.rs
index 0749ac4..49e1392 100644
--- a/src/ui/chat/tree.rs
+++ b/src/ui/chat/tree.rs
@@ -12,7 +12,7 @@ use std::sync::Arc;
 use async_trait::async_trait;
 use parking_lot::FairMutex;
 use tokio::sync::Mutex;
-use toss::{Frame, Pos, Size, Terminal};
+use toss::{Frame, Pos, Size, Terminal, WidthDb};
 
 use crate::macros::logging_unwrap;
 use crate::store::{Msg, MsgStore};
@@ -427,12 +427,17 @@ pub struct TreeView<M: Msg, S: MsgStore<M>> {
 #[async_trait]
 impl<M, S> Widget for TreeView<M, S>
 where
-    M: Msg + ChatMsg,
+    M: Msg + ChatMsg + Send + Sync,
     M::Id: Send + Sync,
     S: MsgStore<M> + Send + Sync,
     S::Error: fmt::Display,
 {
-    fn size(&self, _frame: &mut Frame, _max_width: Option<u16>, _max_height: Option<u16>) -> Size {
+    async fn size(
+        &self,
+        _widthdb: &mut WidthDb,
+        _max_width: Option<u16>,
+        _max_height: Option<u16>,
+    ) -> Size {
         Size::ZERO
     }
 
diff --git a/src/ui/chat/tree/layout.rs b/src/ui/chat/tree/layout.rs
index f474bf9..df5fa4a 100644
--- a/src/ui/chat/tree/layout.rs
+++ b/src/ui/chat/tree/layout.rs
@@ -1,3 +1,4 @@
+use async_recursion::async_recursion;
 use toss::Frame;
 
 use crate::store::{Msg, MsgStore, Path, Tree};
@@ -21,7 +22,12 @@ struct Context {
     focused: bool,
 }
 
-impl<M: Msg + ChatMsg, S: MsgStore<M>> InnerTreeViewState<M, S> {
+impl<M, S> InnerTreeViewState<M, S>
+where
+    M: Msg + ChatMsg + Send + Sync,
+    M::Id: Send + Sync,
+    S: MsgStore<M> + Send + Sync,
+{
     async fn cursor_path(&self, cursor: &Cursor<M::Id>) -> Result<Path<M::Id>, S::Error> {
         Ok(match cursor {
             Cursor::Msg(id) => self.store.path(id).await?,
@@ -69,7 +75,7 @@ impl<M: Msg + ChatMsg, S: MsgStore<M>> InnerTreeViewState<M, S> {
             .is_some()
     }
 
-    fn editor_block(
+    async fn editor_block(
         &self,
         context: &Context,
         frame: &mut Frame,
@@ -78,20 +84,23 @@ impl<M: Msg + ChatMsg, S: MsgStore<M>> InnerTreeViewState<M, S> {
         let (widget, cursor_row) =
             widgets::editor::<M>(frame.widthdb(), indent, &context.nick, &self.editor);
         let cursor_row = cursor_row as i32;
-        Block::new(frame, BlockId::Cursor, widget).focus(cursor_row..cursor_row + 1)
+        Block::new(frame, BlockId::Cursor, widget)
+            .await
+            .focus(cursor_row..cursor_row + 1)
     }
 
-    fn pseudo_block(
+    async fn pseudo_block(
         &self,
         context: &Context,
         frame: &mut Frame,
         indent: usize,
     ) -> Block<BlockId<M::Id>> {
         let widget = widgets::pseudo::<M>(indent, &context.nick, &self.editor);
-        Block::new(frame, BlockId::Cursor, widget)
+        Block::new(frame, BlockId::Cursor, widget).await
     }
 
-    fn layout_subtree(
+    #[async_recursion]
+    async fn layout_subtree(
         &self,
         context: &Context,
         frame: &mut Frame,
@@ -102,7 +111,7 @@ impl<M: Msg + ChatMsg, S: MsgStore<M>> InnerTreeViewState<M, S> {
     ) {
         // Ghost cursor in front, for positioning according to last cursor line
         if self.last_cursor.refers_to(id) {
-            let block = Block::new(frame, BlockId::LastCursor, Empty::new());
+            let block = Block::new(frame, BlockId::LastCursor, Empty::new()).await;
             blocks.blocks_mut().push_back(block);
         }
 
@@ -121,43 +130,40 @@ impl<M: Msg + ChatMsg, S: MsgStore<M>> InnerTreeViewState<M, S> {
         } else {
             widgets::msg_placeholder(highlighted, indent, folded_info)
         };
-        let block = Block::new(frame, BlockId::Msg(id.clone()), widget);
+        let block = Block::new(frame, BlockId::Msg(id.clone()), widget).await;
         blocks.blocks_mut().push_back(block);
 
         // Children, recursively
         if !folded {
             if let Some(children) = tree.children(id) {
                 for child in children {
-                    self.layout_subtree(context, frame, tree, indent + 1, child, blocks);
+                    self.layout_subtree(context, frame, tree, indent + 1, child, blocks)
+                        .await;
                 }
             }
         }
 
         // Trailing ghost cursor, for positioning according to last cursor line
         if self.last_cursor.refers_to_last_child_of(id) {
-            let block = Block::new(frame, BlockId::LastCursor, Empty::new());
+            let block = Block::new(frame, BlockId::LastCursor, Empty::new()).await;
             blocks.blocks_mut().push_back(block);
         }
 
         // Trailing editor or pseudomessage
         if self.cursor.refers_to_last_child_of(id) {
             match self.cursor {
-                Cursor::Editor { .. } => {
-                    blocks
-                        .blocks_mut()
-                        .push_back(self.editor_block(context, frame, indent + 1))
-                }
-                Cursor::Pseudo { .. } => {
-                    blocks
-                        .blocks_mut()
-                        .push_back(self.pseudo_block(context, frame, indent + 1))
-                }
+                Cursor::Editor { .. } => blocks
+                    .blocks_mut()
+                    .push_back(self.editor_block(context, frame, indent + 1).await),
+                Cursor::Pseudo { .. } => blocks
+                    .blocks_mut()
+                    .push_back(self.pseudo_block(context, frame, indent + 1).await),
                 _ => {}
             }
         }
     }
 
-    fn layout_tree(
+    async fn layout_tree(
         &self,
         context: &Context,
         frame: &mut Frame,
@@ -165,32 +171,33 @@ impl<M: Msg + ChatMsg, S: MsgStore<M>> InnerTreeViewState<M, S> {
     ) -> TreeBlocks<M::Id> {
         let root = Root::Tree(tree.root().clone());
         let mut blocks = TreeBlocks::new(root.clone(), root);
-        self.layout_subtree(context, frame, &tree, 0, tree.root(), &mut blocks);
+        self.layout_subtree(context, frame, &tree, 0, tree.root(), &mut blocks)
+            .await;
         blocks
     }
 
-    fn layout_bottom(&self, context: &Context, frame: &mut Frame) -> TreeBlocks<M::Id> {
+    async fn layout_bottom(&self, context: &Context, frame: &mut Frame) -> TreeBlocks<M::Id> {
         let mut blocks = TreeBlocks::new(Root::Bottom, Root::Bottom);
 
         // Ghost cursor, for positioning according to last cursor line
         if let Cursor::Editor { parent: None, .. } | Cursor::Pseudo { parent: None, .. } =
             self.last_cursor
         {
-            let block = Block::new(frame, BlockId::LastCursor, Empty::new());
+            let block = Block::new(frame, BlockId::LastCursor, Empty::new()).await;
             blocks.blocks_mut().push_back(block);
         }
 
         match self.cursor {
             Cursor::Bottom => {
-                let block = Block::new(frame, BlockId::Cursor, Empty::new());
+                let block = Block::new(frame, BlockId::Cursor, Empty::new()).await;
                 blocks.blocks_mut().push_back(block);
             }
             Cursor::Editor { parent: None, .. } => blocks
                 .blocks_mut()
-                .push_back(self.editor_block(context, frame, 0)),
+                .push_back(self.editor_block(context, frame, 0).await),
             Cursor::Pseudo { parent: None, .. } => blocks
                 .blocks_mut()
-                .push_back(self.pseudo_block(context, frame, 0)),
+                .push_back(self.pseudo_block(context, frame, 0).await),
             _ => {}
         }
 
@@ -216,7 +223,7 @@ impl<M: Msg + ChatMsg, S: MsgStore<M>> InnerTreeViewState<M, S> {
                 None => break,
             };
             let prev_tree = self.store.tree(&prev_root_id).await?;
-            blocks.prepend(self.layout_tree(context, frame, prev_tree));
+            blocks.prepend(self.layout_tree(context, frame, prev_tree).await);
         }
 
         Ok(())
@@ -238,9 +245,9 @@ impl<M: Msg + ChatMsg, S: MsgStore<M>> InnerTreeViewState<M, S> {
             };
             if let Some(next_root_id) = next_root_id {
                 let next_tree = self.store.tree(&next_root_id).await?;
-                blocks.append(self.layout_tree(context, frame, next_tree));
+                blocks.append(self.layout_tree(context, frame, next_tree).await);
             } else {
-                blocks.append(self.layout_bottom(context, frame));
+                blocks.append(self.layout_bottom(context, frame).await);
             }
         }
 
@@ -281,7 +288,7 @@ impl<M: Msg + ChatMsg, S: MsgStore<M>> InnerTreeViewState<M, S> {
     ) -> Result<TreeBlocks<M::Id>, S::Error> {
         Ok(match &self.last_cursor {
             Cursor::Bottom => {
-                let mut blocks = self.layout_bottom(context, frame);
+                let mut blocks = self.layout_bottom(context, frame).await;
 
                 let bottom_line = frame.size().height as i32 - 1;
                 blocks.blocks_mut().set_bottom_line(bottom_line);
@@ -289,7 +296,7 @@ impl<M: Msg + ChatMsg, S: MsgStore<M>> InnerTreeViewState<M, S> {
                 blocks
             }
             Cursor::Editor { parent: None, .. } | Cursor::Pseudo { parent: None, .. } => {
-                let mut blocks = self.layout_bottom(context, frame);
+                let mut blocks = self.layout_bottom(context, frame).await;
 
                 blocks
                     .blocks_mut()
@@ -306,7 +313,7 @@ impl<M: Msg + ChatMsg, S: MsgStore<M>> InnerTreeViewState<M, S> {
             } => {
                 let root = last_cursor_path.first();
                 let tree = self.store.tree(root).await?;
-                let mut blocks = self.layout_tree(context, frame, tree);
+                let mut blocks = self.layout_tree(context, frame, tree).await;
 
                 blocks
                     .blocks_mut()
@@ -330,7 +337,7 @@ impl<M: Msg + ChatMsg, S: MsgStore<M>> InnerTreeViewState<M, S> {
             Cursor::Bottom
             | Cursor::Editor { parent: None, .. }
             | Cursor::Pseudo { parent: None, .. } => {
-                let mut blocks = self.layout_bottom(context, frame);
+                let mut blocks = self.layout_bottom(context, frame).await;
 
                 blocks.blocks_mut().set_bottom_line(bottom_line);
 
@@ -345,7 +352,7 @@ impl<M: Msg + ChatMsg, S: MsgStore<M>> InnerTreeViewState<M, S> {
             } => {
                 let root = cursor_path.first();
                 let tree = self.store.tree(root).await?;
-                let mut blocks = self.layout_tree(context, frame, tree);
+                let mut blocks = self.layout_tree(context, frame, tree).await;
 
                 let cursor_above_last = cursor_path < last_cursor_path;
                 let cursor_line = if cursor_above_last { 0 } else { bottom_line };
diff --git a/src/ui/chat/tree/widgets/indent.rs b/src/ui/chat/tree/widgets/indent.rs
index 4e120c6..a226f93 100644
--- a/src/ui/chat/tree/widgets/indent.rs
+++ b/src/ui/chat/tree/widgets/indent.rs
@@ -1,5 +1,5 @@
 use async_trait::async_trait;
-use toss::{Frame, Pos, Size, Style};
+use toss::{Frame, Pos, Size, Style, WidthDb};
 
 use crate::ui::widgets::Widget;
 
@@ -19,7 +19,12 @@ impl Indent {
 
 #[async_trait]
 impl Widget for Indent {
-    fn size(&self, _frame: &mut Frame, _max_width: Option<u16>, _max_height: Option<u16>) -> Size {
+    async fn size(
+        &self,
+        _widthdb: &mut WidthDb,
+        _max_width: Option<u16>,
+        _max_height: Option<u16>,
+    ) -> Size {
         Size::new((INDENT_WIDTH * self.level) as u16, 0)
     }
 
diff --git a/src/ui/widgets.rs b/src/ui/widgets.rs
index f5cb59c..20fb6d3 100644
--- a/src/ui/widgets.rs
+++ b/src/ui/widgets.rs
@@ -19,20 +19,25 @@ pub mod rules;
 pub mod text;
 
 use async_trait::async_trait;
-use toss::{Frame, Size};
+use toss::{Frame, Size, WidthDb};
 
 // TODO Add Error type and return Result-s (at least in Widget::render)
 
 #[async_trait]
 pub trait Widget {
-    fn size(&self, frame: &mut Frame, max_width: Option<u16>, max_height: Option<u16>) -> Size;
+    async fn size(
+        &self,
+        widthdb: &mut WidthDb,
+        max_width: Option<u16>,
+        max_height: Option<u16>,
+    ) -> Size;
 
     async fn render(self: Box<Self>, frame: &mut Frame);
 }
 
-pub type BoxedWidget = Box<dyn Widget + Send>;
+pub type BoxedWidget = Box<dyn Widget + Send + Sync>;
 
-impl<W: 'static + Widget + Send> From<W> for BoxedWidget {
+impl<W: 'static + Widget + Send + Sync> From<W> for BoxedWidget {
     fn from(widget: W) -> Self {
         Box::new(widget)
     }
diff --git a/src/ui/widgets/background.rs b/src/ui/widgets/background.rs
index f075a91..432e54d 100644
--- a/src/ui/widgets/background.rs
+++ b/src/ui/widgets/background.rs
@@ -1,5 +1,5 @@
 use async_trait::async_trait;
-use toss::{Frame, Pos, Size, Style};
+use toss::{Frame, Pos, Size, Style, WidthDb};
 
 use super::{BoxedWidget, Widget};
 
@@ -24,8 +24,13 @@ impl Background {
 
 #[async_trait]
 impl Widget for Background {
-    fn size(&self, frame: &mut Frame, max_width: Option<u16>, max_height: Option<u16>) -> Size {
-        self.inner.size(frame, max_width, max_height)
+    async fn size(
+        &self,
+        widthdb: &mut WidthDb,
+        max_width: Option<u16>,
+        max_height: Option<u16>,
+    ) -> Size {
+        self.inner.size(widthdb, max_width, max_height).await
     }
 
     async fn render(self: Box<Self>, frame: &mut Frame) {
diff --git a/src/ui/widgets/border.rs b/src/ui/widgets/border.rs
index 134312b..bfd76ea 100644
--- a/src/ui/widgets/border.rs
+++ b/src/ui/widgets/border.rs
@@ -1,5 +1,5 @@
 use async_trait::async_trait;
-use toss::{Frame, Pos, Size, Style};
+use toss::{Frame, Pos, Size, Style, WidthDb};
 
 use super::{BoxedWidget, Widget};
 
@@ -24,10 +24,15 @@ impl Border {
 
 #[async_trait]
 impl Widget for Border {
-    fn size(&self, frame: &mut Frame, max_width: Option<u16>, max_height: Option<u16>) -> Size {
+    async fn size(
+        &self,
+        widthdb: &mut WidthDb,
+        max_width: Option<u16>,
+        max_height: Option<u16>,
+    ) -> Size {
         let max_width = max_width.map(|w| w.saturating_sub(2));
         let max_height = max_height.map(|h| h.saturating_sub(2));
-        let size = self.inner.size(frame, max_width, max_height);
+        let size = self.inner.size(widthdb, max_width, max_height).await;
         size + Size::new(2, 2)
     }
 
diff --git a/src/ui/widgets/cursor.rs b/src/ui/widgets/cursor.rs
index 09856f4..22ac5cc 100644
--- a/src/ui/widgets/cursor.rs
+++ b/src/ui/widgets/cursor.rs
@@ -1,5 +1,5 @@
 use async_trait::async_trait;
-use toss::{Frame, Pos, Size};
+use toss::{Frame, Pos, Size, WidthDb};
 
 use super::{BoxedWidget, Widget};
 
@@ -28,8 +28,13 @@ impl Cursor {
 
 #[async_trait]
 impl Widget for Cursor {
-    fn size(&self, frame: &mut Frame, max_width: Option<u16>, max_height: Option<u16>) -> Size {
-        self.inner.size(frame, max_width, max_height)
+    async fn size(
+        &self,
+        widthdb: &mut WidthDb,
+        max_width: Option<u16>,
+        max_height: Option<u16>,
+    ) -> Size {
+        self.inner.size(widthdb, max_width, max_height).await
     }
 
     async fn render(self: Box<Self>, frame: &mut Frame) {
diff --git a/src/ui/widgets/editor.rs b/src/ui/widgets/editor.rs
index 088373e..e2b8955 100644
--- a/src/ui/widgets/editor.rs
+++ b/src/ui/widgets/editor.rs
@@ -493,9 +493,14 @@ impl Editor {
 
 #[async_trait]
 impl Widget for Editor {
-    fn size(&self, frame: &mut Frame, max_width: Option<u16>, max_height: Option<u16>) -> Size {
+    async fn size(
+        &self,
+        widthdb: &mut WidthDb,
+        max_width: Option<u16>,
+        max_height: Option<u16>,
+    ) -> Size {
         if let Some(placeholder) = &self.hidden {
-            let mut size = placeholder.size(frame, max_width, max_height);
+            let mut size = placeholder.size(widthdb, max_width, max_height).await;
 
             // Cursor needs to fit regardless of focus
             size.width = size.width.max(1);
@@ -504,8 +509,6 @@ impl Widget for Editor {
             return size;
         }
 
-        let widthdb = frame.widthdb();
-
         let max_width = max_width.map(|w| w as usize).unwrap_or(usize::MAX).max(1);
         let max_text_width = max_width - 1;
         let indices = wrap(widthdb, self.text.text(), max_text_width);
diff --git a/src/ui/widgets/empty.rs b/src/ui/widgets/empty.rs
index 790c8b1..a5d98ea 100644
--- a/src/ui/widgets/empty.rs
+++ b/src/ui/widgets/empty.rs
@@ -1,5 +1,5 @@
 use async_trait::async_trait;
-use toss::{Frame, Size};
+use toss::{Frame, Size, WidthDb};
 
 use super::Widget;
 
@@ -31,7 +31,12 @@ impl Empty {
 
 #[async_trait]
 impl Widget for Empty {
-    fn size(&self, _frame: &mut Frame, _max_width: Option<u16>, _max_height: Option<u16>) -> Size {
+    async fn size(
+        &self,
+        _widthdb: &mut WidthDb,
+        _max_width: Option<u16>,
+        _max_height: Option<u16>,
+    ) -> Size {
         self.size
     }
 
diff --git a/src/ui/widgets/float.rs b/src/ui/widgets/float.rs
index 6a82284..a262cd6 100644
--- a/src/ui/widgets/float.rs
+++ b/src/ui/widgets/float.rs
@@ -1,5 +1,5 @@
 use async_trait::async_trait;
-use toss::{Frame, Pos, Size};
+use toss::{Frame, Pos, Size, WidthDb};
 
 use super::{BoxedWidget, Widget};
 
@@ -31,14 +31,22 @@ impl Float {
 
 #[async_trait]
 impl Widget for Float {
-    fn size(&self, frame: &mut Frame, max_width: Option<u16>, max_height: Option<u16>) -> Size {
-        self.inner.size(frame, max_width, max_height)
+    async fn size(
+        &self,
+        widthdb: &mut WidthDb,
+        max_width: Option<u16>,
+        max_height: Option<u16>,
+    ) -> Size {
+        self.inner.size(widthdb, max_width, max_height).await
     }
 
     async fn render(self: Box<Self>, frame: &mut Frame) {
         let size = frame.size();
 
-        let mut inner_size = self.inner.size(frame, Some(size.width), Some(size.height));
+        let mut inner_size = self
+            .inner
+            .size(frame.widthdb(), Some(size.width), Some(size.height))
+            .await;
         inner_size.width = inner_size.width.min(size.width);
         inner_size.height = inner_size.height.min(size.height);
 
diff --git a/src/ui/widgets/join.rs b/src/ui/widgets/join.rs
index 00d18fa..2aa4551 100644
--- a/src/ui/widgets/join.rs
+++ b/src/ui/widgets/join.rs
@@ -1,5 +1,5 @@
 use async_trait::async_trait;
-use toss::{Frame, Pos, Size};
+use toss::{Frame, Pos, Size, WidthDb};
 
 use super::{BoxedWidget, Widget};
 
@@ -54,9 +54,9 @@ impl SizedSegment {
     }
 }
 
-fn sizes_horiz(
+async fn sizes_horiz(
     segments: &[Segment],
-    frame: &mut Frame,
+    widthdb: &mut WidthDb,
     max_width: Option<u16>,
     max_height: Option<u16>,
 ) -> Vec<SizedSegment> {
@@ -74,7 +74,8 @@ fn sizes_horiz(
             .map(|w| w.saturating_sub(total_width));
         s.size = segments[s.idx]
             .widget
-            .size(frame, available_width, max_height);
+            .size(widthdb, available_width, max_height)
+            .await;
         if let Some(available_width) = available_width {
             s.size.width = s.size.width.min(available_width);
         }
@@ -84,9 +85,9 @@ fn sizes_horiz(
     sized
 }
 
-fn sizes_vert(
+async fn sizes_vert(
     segments: &[Segment],
-    frame: &mut Frame,
+    widthdb: &mut WidthDb,
     max_width: Option<u16>,
     max_height: Option<u16>,
 ) -> Vec<SizedSegment> {
@@ -104,7 +105,8 @@ fn sizes_vert(
             .map(|w| w.saturating_sub(total_height));
         s.size = segments[s.idx]
             .widget
-            .size(frame, max_width, available_height);
+            .size(widthdb, max_width, available_height)
+            .await;
         if let Some(available_height) = available_height {
             s.size.height = s.size.height.min(available_height);
         }
@@ -177,8 +179,13 @@ impl HJoin {
 
 #[async_trait]
 impl Widget for HJoin {
-    fn size(&self, frame: &mut Frame, max_width: Option<u16>, max_height: Option<u16>) -> Size {
-        let sizes = sizes_horiz(&self.segments, frame, max_width, max_height);
+    async fn size(
+        &self,
+        widthdb: &mut WidthDb,
+        max_width: Option<u16>,
+        max_height: Option<u16>,
+    ) -> Size {
+        let sizes = sizes_horiz(&self.segments, widthdb, max_width, max_height).await;
         let width = sizes.iter().map(|s| s.size.width).sum::<u16>();
         let height = sizes.iter().map(|s| s.size.height).max().unwrap_or(0);
         Size::new(width, height)
@@ -187,7 +194,13 @@ impl Widget for HJoin {
     async fn render(self: Box<Self>, frame: &mut Frame) {
         let size = frame.size();
 
-        let mut sizes = sizes_horiz(&self.segments, frame, Some(size.width), Some(size.height));
+        let mut sizes = sizes_horiz(
+            &self.segments,
+            frame.widthdb(),
+            Some(size.width),
+            Some(size.height),
+        )
+        .await;
         expand_horiz(&mut sizes, size.width);
 
         sizes.sort_by_key(|s| s.idx);
@@ -215,8 +228,13 @@ impl VJoin {
 
 #[async_trait]
 impl Widget for VJoin {
-    fn size(&self, frame: &mut Frame, max_width: Option<u16>, max_height: Option<u16>) -> Size {
-        let sizes = sizes_vert(&self.segments, frame, max_width, max_height);
+    async fn size(
+        &self,
+        widthdb: &mut WidthDb,
+        max_width: Option<u16>,
+        max_height: Option<u16>,
+    ) -> Size {
+        let sizes = sizes_vert(&self.segments, widthdb, max_width, max_height).await;
         let width = sizes.iter().map(|s| s.size.width).max().unwrap_or(0);
         let height = sizes.iter().map(|s| s.size.height).sum::<u16>();
         Size::new(width, height)
@@ -225,7 +243,13 @@ impl Widget for VJoin {
     async fn render(self: Box<Self>, frame: &mut Frame) {
         let size = frame.size();
 
-        let mut sizes = sizes_vert(&self.segments, frame, Some(size.width), Some(size.height));
+        let mut sizes = sizes_vert(
+            &self.segments,
+            frame.widthdb(),
+            Some(size.width),
+            Some(size.height),
+        )
+        .await;
         expand_vert(&mut sizes, size.height);
 
         sizes.sort_by_key(|s| s.idx);
diff --git a/src/ui/widgets/layer.rs b/src/ui/widgets/layer.rs
index 30807e6..fe0d983 100644
--- a/src/ui/widgets/layer.rs
+++ b/src/ui/widgets/layer.rs
@@ -1,5 +1,5 @@
 use async_trait::async_trait;
-use toss::{Frame, Size};
+use toss::{Frame, Size, WidthDb};
 
 use super::{BoxedWidget, Widget};
 
@@ -15,10 +15,15 @@ impl Layer {
 
 #[async_trait]
 impl Widget for Layer {
-    fn size(&self, frame: &mut Frame, max_width: Option<u16>, max_height: Option<u16>) -> Size {
+    async fn size(
+        &self,
+        widthdb: &mut WidthDb,
+        max_width: Option<u16>,
+        max_height: Option<u16>,
+    ) -> Size {
         let mut max_size = Size::ZERO;
         for layer in &self.layers {
-            let size = layer.size(frame, max_width, max_height);
+            let size = layer.size(widthdb, max_width, max_height).await;
             max_size.width = max_size.width.max(size.width);
             max_size.height = max_size.height.max(size.height);
         }
diff --git a/src/ui/widgets/list.rs b/src/ui/widgets/list.rs
index 0dcd0aa..fc148a0 100644
--- a/src/ui/widgets/list.rs
+++ b/src/ui/widgets/list.rs
@@ -2,7 +2,7 @@ use std::sync::Arc;
 
 use async_trait::async_trait;
 use parking_lot::Mutex;
-use toss::{Frame, Pos, Size};
+use toss::{Frame, Pos, Size, WidthDb};
 
 use super::{BoxedWidget, Widget};
 
@@ -266,14 +266,19 @@ impl<Id> Row<Id> {
         }
     }
 
-    fn size(&self, frame: &mut Frame, max_width: Option<u16>, max_height: Option<u16>) -> Size {
+    async fn size(
+        &self,
+        widthdb: &mut WidthDb,
+        max_width: Option<u16>,
+        max_height: Option<u16>,
+    ) -> Size {
         match self {
-            Self::Unselectable { normal } => normal.size(frame, max_width, max_height),
+            Self::Unselectable { normal } => normal.size(widthdb, max_width, max_height).await,
             Self::Selectable {
                 normal, selected, ..
             } => {
-                let normal_size = normal.size(frame, max_width, max_height);
-                let selected_size = selected.size(frame, max_width, max_height);
+                let normal_size = normal.size(widthdb, max_width, max_height).await;
+                let selected_size = selected.size(widthdb, max_width, max_height).await;
                 Size::new(
                     normal_size.width.max(selected_size.width),
                     normal_size.height.max(selected_size.height),
@@ -327,14 +332,18 @@ impl<Id> List<Id> {
 }
 
 #[async_trait]
-impl<Id: Clone + Eq + Send> Widget for List<Id> {
-    fn size(&self, frame: &mut Frame, max_width: Option<u16>, _max_height: Option<u16>) -> Size {
-        let width = self
-            .rows
-            .iter()
-            .map(|r| r.size(frame, max_width, Some(1)).width)
-            .max()
-            .unwrap_or(0);
+impl<Id: Clone + Eq + Send + Sync> Widget for List<Id> {
+    async fn size(
+        &self,
+        widthdb: &mut WidthDb,
+        max_width: Option<u16>,
+        _max_height: Option<u16>,
+    ) -> Size {
+        let mut width = 0;
+        for row in &self.rows {
+            let size = row.size(widthdb, max_width, Some(1)).await;
+            width = width.max(size.width);
+        }
         let height = self.rows.len();
         Size::new(width, height as u16)
     }
diff --git a/src/ui/widgets/padding.rs b/src/ui/widgets/padding.rs
index e2be11d..e5b45cd 100644
--- a/src/ui/widgets/padding.rs
+++ b/src/ui/widgets/padding.rs
@@ -1,5 +1,5 @@
 use async_trait::async_trait;
-use toss::{Frame, Pos, Size};
+use toss::{Frame, Pos, Size, WidthDb};
 
 use super::{BoxedWidget, Widget};
 
@@ -66,14 +66,19 @@ impl Padding {
 
 #[async_trait]
 impl Widget for Padding {
-    fn size(&self, frame: &mut Frame, max_width: Option<u16>, max_height: Option<u16>) -> Size {
+    async fn size(
+        &self,
+        widthdb: &mut WidthDb,
+        max_width: Option<u16>,
+        max_height: Option<u16>,
+    ) -> Size {
         let horizontal = self.left + self.right;
         let vertical = self.top + self.bottom;
 
         let max_width = max_width.map(|w| w.saturating_sub(horizontal));
         let max_height = max_height.map(|h| h.saturating_sub(vertical));
 
-        let size = self.inner.size(frame, max_width, max_height);
+        let size = self.inner.size(widthdb, max_width, max_height).await;
 
         size + Size::new(horizontal, vertical)
     }
diff --git a/src/ui/widgets/resize.rs b/src/ui/widgets/resize.rs
index 67c07ed..b2edf22 100644
--- a/src/ui/widgets/resize.rs
+++ b/src/ui/widgets/resize.rs
@@ -1,5 +1,5 @@
 use async_trait::async_trait;
-use toss::{Frame, Size};
+use toss::{Frame, Size, WidthDb};
 
 use super::{BoxedWidget, Widget};
 
@@ -45,7 +45,12 @@ impl Resize {
 
 #[async_trait]
 impl Widget for Resize {
-    fn size(&self, frame: &mut Frame, max_width: Option<u16>, max_height: Option<u16>) -> Size {
+    async fn size(
+        &self,
+        widthdb: &mut WidthDb,
+        max_width: Option<u16>,
+        max_height: Option<u16>,
+    ) -> Size {
         let max_width = match (max_width, self.max_width) {
             (None, None) => None,
             (Some(w), None) => Some(w),
@@ -60,7 +65,7 @@ impl Widget for Resize {
             (Some(h), Some(sh)) => Some(h.min(sh)),
         };
 
-        let size = self.inner.size(frame, max_width, max_height);
+        let size = self.inner.size(widthdb, max_width, max_height).await;
 
         let width = match self.min_width {
             Some(min_width) => size.width.max(min_width),
diff --git a/src/ui/widgets/rules.rs b/src/ui/widgets/rules.rs
index f6b01c1..eaff35f 100644
--- a/src/ui/widgets/rules.rs
+++ b/src/ui/widgets/rules.rs
@@ -1,5 +1,5 @@
 use async_trait::async_trait;
-use toss::{Frame, Pos, Size};
+use toss::{Frame, Pos, Size, WidthDb};
 
 use super::Widget;
 
@@ -7,7 +7,12 @@ pub struct HRule;
 
 #[async_trait]
 impl Widget for HRule {
-    fn size(&self, _frame: &mut Frame, _max_width: Option<u16>, _max_height: Option<u16>) -> Size {
+    async fn size(
+        &self,
+        _widthdb: &mut WidthDb,
+        _max_width: Option<u16>,
+        _max_height: Option<u16>,
+    ) -> Size {
         Size::new(0, 1)
     }
 
@@ -23,7 +28,12 @@ pub struct VRule;
 
 #[async_trait]
 impl Widget for VRule {
-    fn size(&self, _frame: &mut Frame, _max_width: Option<u16>, _max_height: Option<u16>) -> Size {
+    async fn size(
+        &self,
+        _widthdb: &mut WidthDb,
+        _max_width: Option<u16>,
+        _max_height: Option<u16>,
+    ) -> Size {
         Size::new(1, 0)
     }
 
diff --git a/src/ui/widgets/text.rs b/src/ui/widgets/text.rs
index 1a383f5..3ce1dbe 100644
--- a/src/ui/widgets/text.rs
+++ b/src/ui/widgets/text.rs
@@ -36,9 +36,13 @@ impl Text {
 
 #[async_trait]
 impl Widget for Text {
-    fn size(&self, frame: &mut Frame, max_width: Option<u16>, _max_height: Option<u16>) -> Size {
-        let lines = self.wrapped(frame.widthdb(), max_width);
-        let widthdb = frame.widthdb();
+    async fn size(
+        &self,
+        widthdb: &mut WidthDb,
+        max_width: Option<u16>,
+        _max_height: Option<u16>,
+    ) -> Size {
+        let lines = self.wrapped(widthdb, max_width);
         let min_width = lines
             .iter()
             .map(|l| widthdb.width(l.text().trim_end()))