diff --git a/src/compiler/compile/render_dom/wrappers/Title.ts b/src/compiler/compile/render_dom/wrappers/Title.ts
index f24c7f02ad..a97df1c330 100644
--- a/src/compiler/compile/render_dom/wrappers/Title.ts
+++ b/src/compiler/compile/render_dom/wrappers/Title.ts
@@ -1,98 +1,93 @@
 import { b, x } from 'code-red';
-import Wrapper from './shared/Wrapper';
-import Renderer from '../Renderer';
-import Block from '../Block';
-import Title from '../../nodes/Title';
-import { string_literal } from '../../utils/stringify';
-import add_to_set from '../../utils/add_to_set';
-import Text from '../../nodes/Text';
-import { Identifier } from 'estree';
-import MustacheTag from '../../nodes/MustacheTag';
+import Wrapper from './shared/Wrapper.js';
+import { string_literal } from '../../utils/stringify.js';
+import add_to_set from '../../utils/add_to_set.js';
 
+/** @extends Wrapper */
 export default class TitleWrapper extends Wrapper {
-	node: Title;
 
-	constructor(
-		renderer: Renderer,
-		block: Block,
-		parent: Wrapper,
-		node: Title,
-		_strip_whitespace: boolean,
-		_next_sibling: Wrapper
-	) {
-		super(renderer, block, parent, node);
-	}
-
-	render(block: Block, _parent_node: Identifier, _parent_nodes: Identifier) {
-		const is_dynamic = !!this.node.children.find((node) => node.type !== 'Text');
-
-		if (is_dynamic) {
-			let value;
-
-			const all_dependencies: Set<string> = new Set();
-
-			// TODO some of this code is repeated in Tag.ts — would be good to
-			// DRY it out if that's possible without introducing crazy indirection
-			if (this.node.children.length === 1) {
-				// single {tag} — may be a non-string
-				// @ts-ignore todo: check this
-				const { expression } = this.node.children[0];
-				value = expression.manipulate(block);
-				add_to_set(all_dependencies, expression.dependencies);
-			} else {
-				// '{foo} {bar}' — treat as string concatenation
-				value = this.node.children
-					.map((chunk) => {
-						if (chunk.type === 'Text') return string_literal(chunk.data);
-
-						(chunk as MustacheTag).expression.dependencies.forEach((d) => {
-							all_dependencies.add(d);
-						});
-
-						return (chunk as MustacheTag).expression.manipulate(block);
-					})
-					.reduce((lhs, rhs) => x`${lhs} + ${rhs}`);
-
-				if (this.node.children[0].type !== 'Text') {
-					value = x`"" + ${value}`;
-				}
-			}
-
-			const last = this.node.should_cache && block.get_unique_name('title_value');
-
-			if (this.node.should_cache) block.add_variable(last);
-
-			const init = this.node.should_cache ? x`${last} = ${value}` : value;
-
-			block.chunks.init.push(b`@_document.title = ${init};`);
-
-			const updater = b`@_document.title = ${this.node.should_cache ? last : value};`;
-
-			if (all_dependencies.size) {
-				const dependencies = Array.from(all_dependencies);
-
-				let condition = block.renderer.dirty(dependencies);
-
-				if (block.has_outros) {
-					condition = x`!#current || ${condition}`;
-				}
-
-				if (this.node.should_cache) {
-					condition = x`${condition} && (${last} !== (${last} = ${value}))`;
-				}
-
-				block.chunks.update.push(b`
+    /** @type {import('../../nodes/Title.js').default} */
+    node;
+
+ /**
+  * @param {import('../Renderer.js').default} renderer
+     * @param {import('../Block.js').default} block
+     * @param {import('./shared/Wrapper.js').default} parent
+     * @param {import('../../nodes/Title.js').default} node
+     * @param {boolean} _strip_whitespace
+     * @param {import('./shared/Wrapper.js').default} _next_sibling
+     */
+    constructor(renderer, block, parent, node, _strip_whitespace, _next_sibling) {
+        super(renderer, block, parent, node);
+    }
+
+ /**
+  * @param {import('../Block.js').default} block
+     * @param {import('estree').Identifier} _parent_node
+     * @param {import('estree').Identifier} _parent_nodes
+     */
+    render(block, _parent_node, _parent_nodes) {
+        const is_dynamic = !!this.node.children.find((node) => node.type !== 'Text');
+        if (is_dynamic) {
+            let value;
+
+            /** @type {Set<string>} */
+            const all_dependencies = new Set();
+            // TODO some of this code is repeated in Tag.ts — would be good to
+            // DRY it out if that's possible without introducing crazy indirection
+            if (this.node.children.length === 1) {
+                // single {tag} — may be a non-string
+                // @ts-ignore todo: check this
+                const { expression } = this.node.children[0];
+                value = expression.manipulate(block);
+                add_to_set(all_dependencies, expression.dependencies);
+            }
+            else {
+                // '{foo} {bar}' — treat as string concatenation
+                value = this.node.children
+                    .map((chunk) => {
+                    if (chunk.type === 'Text')
+                        return string_literal(chunk.data);
+                    ( /** @type {import('../../nodes/MustacheTag.js').default} */(chunk)).expression.dependencies.forEach((d) => {
+                        all_dependencies.add(d);
+                    });
+                    return ( /** @type {import('../../nodes/MustacheTag.js').default} */(chunk)).expression.manipulate(block);
+                })
+                    .reduce((lhs, rhs) => x `${lhs} + ${rhs}`);
+                if (this.node.children[0].type !== 'Text') {
+                    value = x `"" + ${value}`;
+                }
+            }
+            const last = this.node.should_cache && block.get_unique_name('title_value');
+            if (this.node.should_cache)
+                block.add_variable(last);
+            const init = this.node.should_cache ? x `${last} = ${value}` : value;
+            block.chunks.init.push(b `@_document.title = ${init};`);
+            const updater = b `@_document.title = ${this.node.should_cache ? last : value};`;
+            if (all_dependencies.size) {
+                const dependencies = Array.from(all_dependencies);
+                let condition = block.renderer.dirty(dependencies);
+                if (block.has_outros) {
+                    condition = x `!#current || ${condition}`;
+                }
+                if (this.node.should_cache) {
+                    condition = x `${condition} && (${last} !== (${last} = ${value}))`;
+                }
+                block.chunks.update.push(b `
 					if (${condition}) {
 						${updater}
 					}`);
-			}
-		} else {
-			const value =
-				this.node.children.length > 0
-					? string_literal((this.node.children[0] as Text).data)
-					: x`""`;
-
-			block.chunks.hydrate.push(b`@_document.title = ${value};`);
-		}
-	}
+            }
+        }
+        else {
+            const value = this.node.children.length > 0
+                ? string_literal(( /** @type {import('../../nodes/Text.js').default} */(this.node.children[0])).data)
+                : x `""`;
+            block.chunks.hydrate.push(b `@_document.title = ${value};`);
+        }
+    }
 }
+
+
+
+