diff --git a/packages/coding-agent/CHANGELOG.md b/packages/coding-agent/CHANGELOG.md
index a49d1c64e..aadb5227e 100644
--- a/packages/coding-agent/CHANGELOG.md
+++ b/packages/coding-agent/CHANGELOG.md
@@ -1,7 +1,6 @@
 # Changelog
 
 ## [Unreleased]
-
 ### Added
 
 - Added `replace` hashline edit operation for substr-style fuzzy text replacement without line references, with optional `all` flag for replace-all behavior
@@ -58,6 +57,8 @@
 
 ### Fixed
 
+- Fixed resource leak in browser query handler by properly disposing owned proxy elements for non-winning candidates
+- Fixed script evaluation to support async functions and await expressions in browser evaluate operations
 - Fixed `range` edits with missing `end` field to gracefully degrade to single-line edits instead of crashing
 - Fixed `insertAfter` operations to accept both `content` and `replacement` field names for consistency with other edit types
 - Fixed deduplication logic to correctly identify and remove identical hashline edits targeting the same line(s) in a single call
diff --git a/packages/coding-agent/src/tools/browser.ts b/packages/coding-agent/src/tools/browser.ts
index 0f48091c2..0c9d774a1 100644
--- a/packages/coding-agent/src/tools/browser.ts
+++ b/packages/coding-agent/src/tools/browser.ts
@@ -93,7 +93,11 @@ function normalizeSelector(selector: string): string {
 type ActionabilityResult = { ok: true; x: number; y: number } | { ok: false; reason: string };
 
 async function resolveActionableQueryHandlerClickTarget(handles: ElementHandle[]): Promise<ElementHandle | null> {
-	const candidates: Array<{ handle: ElementHandle; rect: { x: number; y: number; w: number; h: number } }> = [];
+	const candidates: Array<{
+		handle: ElementHandle;
+		rect: { x: number; y: number; w: number; h: number };
+		ownedProxy?: ElementHandle;
+	}> = [];
 
 	for (const handle of handles) {
 		let clickable: ElementHandle = handle;
@@ -123,11 +127,11 @@ async function resolveActionableQueryHandlerClickTarget(handles: ElementHandle[]
 				return { x: r.left, y: r.top, w: r.width, h: r.height };
 			})) as { x: number; y: number; w: number; h: number };
 			if (rect.w < 1 || rect.h < 1) continue;
-			candidates.push({ handle: clickable, rect });
+			candidates.push({ handle: clickable, rect, ownedProxy: clickableProxy ?? undefined });
 		} catch {
 			// ignore
 		} finally {
-			if (clickableProxy && clickableProxy !== handle) {
+			if (clickableProxy && clickableProxy !== handle && clickable !== clickableProxy) {
 				try {
 					await clickableProxy.dispose();
 				} catch {}
@@ -139,7 +143,17 @@ async function resolveActionableQueryHandlerClickTarget(handles: ElementHandle[]
 
 	// Prefer top-most visible element (nav/header usually wins), tie-break by left-most.
 	candidates.sort((a, b) => a.rect.y - b.rect.y || a.rect.x - b.rect.x);
-	return candidates[0]?.handle ?? null;
+	const winner = candidates[0]?.handle ?? null;
+	// Dispose owned proxies for non-winning candidates
+	for (let i = 1; i < candidates.length; i++) {
+		const c = candidates[i]!;
+		if (c.ownedProxy) {
+			try {
+				await c.ownedProxy.dispose();
+			} catch {}
+		}
+	}
+	return winner;
 }
 
 async function isClickActionable(handle: ElementHandle): Promise<ActionabilityResult> {
@@ -1126,11 +1140,11 @@ export class BrowserTool implements AgentTool<typeof browserSchema, BrowserToolD
 					const script = ensureParam(params.script, "script", params.action);
 					const page = await this.#ensurePage(params);
 					const value = (await untilAborted(signal, () =>
-						page.evaluate((source: string) => {
+						page.evaluate(async (source: string) => {
 							try {
-								return new Function(`return (${source});`)();
+								return await new Function(`return (async () => (${source}))();`)();
 							} catch {
-								return new Function(source)();
+								return await new Function(`return (async () => { ${source} })();`)();
 							}
 						}, script),
 					)) as unknown;
diff --git a/packages/react-edit-benchmark/runner.ts b/packages/react-edit-benchmark/runner.ts
index 86aa26cb9..0e641fb0c 100644
--- a/packages/react-edit-benchmark/runner.ts
+++ b/packages/react-edit-benchmark/runner.ts
@@ -83,7 +83,7 @@ async function collectOriginalFileContents(cwd: string, files: string[]): Promis
 	return originals;
 }
 
-function buildMutationPreviewAgainstOriginal(original: string, current: string, maxLines = 8): string | null {
+function buildMutationPreviewAgainstOriginal(original: string, current: string): string | null {
 	if (original === current) return null;
 
 	const changes = diffLines(original, current);
@@ -102,7 +102,6 @@ function buildMutationPreviewAgainstOriginal(original: string, current: string,
 				const hash = computeLineHash(lineNum, line);
 				preview.push(`${lineNum}:${hash}| -${line}`);
 				lineNum += 1;
-				if (preview.length >= maxLines) return preview.join("\n");
 			}
 			continue;
 		}
@@ -110,7 +109,6 @@ function buildMutationPreviewAgainstOriginal(original: string, current: string,
 		for (const line of lines) {
 			const hash = computeLineHash(lineNum, line);
 			preview.push(`${lineNum}:${hash}| +${line}`);
-			if (preview.length >= maxLines) return preview.join("\n");
 		}
 	}