diff --git a/extensions/browser/src/browser/chrome.profile-decoration.ts b/extensions/browser/src/browser/chrome.profile-decoration.ts
index 8739860e2a4..dd15dca9d5d 100644
--- a/extensions/browser/src/browser/chrome.profile-decoration.ts
+++ b/extensions/browser/src/browser/chrome.profile-decoration.ts
@@ -30,6 +30,16 @@ function safeWriteJson(filePath: string, data: Record<string, unknown>) {
   fs.writeFileSync(filePath, JSON.stringify(data, null, 2));
 }
 
+function asRecord(value: unknown): Record<string, unknown> | null {
+  return typeof value === "object" && value !== null && !Array.isArray(value)
+    ? (value as Record<string, unknown>)
+    : null;
+}
+
+function readNestedRecord(root: unknown, key: string): Record<string, unknown> | null {
+  return asRecord(asRecord(root)?.[key]);
+}
+
 function setDeep(obj: Record<string, unknown>, keys: string[], value: unknown) {
   let node: Record<string, unknown> = obj;
   for (const key of keys.slice(0, -1)) {
@@ -65,42 +75,11 @@ export function isProfileDecorated(
 
   const localState = safeReadJson(localStatePath);
   const profile = localState?.profile;
-  const infoCache =
-    typeof profile === "object" && profile !== null && !Array.isArray(profile)
-      ? (profile as Record<string, unknown>).info_cache
-      : null;
-  const info =
-    typeof infoCache === "object" &&
-    infoCache !== null &&
-    !Array.isArray(infoCache) &&
-    typeof (infoCache as Record<string, unknown>).Default === "object" &&
-    (infoCache as Record<string, unknown>).Default !== null &&
-    !Array.isArray((infoCache as Record<string, unknown>).Default)
-      ? ((infoCache as Record<string, unknown>).Default as Record<string, unknown>)
-      : null;
+  const info = readNestedRecord(readNestedRecord(profile, "info_cache"), "Default");
 
   const prefs = safeReadJson(preferencesPath);
-  const browserTheme = (() => {
-    const browser = prefs?.browser;
-    const theme =
-      typeof browser === "object" && browser !== null && !Array.isArray(browser)
-        ? (browser as Record<string, unknown>).theme
-        : null;
-    return typeof theme === "object" && theme !== null && !Array.isArray(theme)
-      ? (theme as Record<string, unknown>)
-      : null;
-  })();
-
-  const autogeneratedTheme = (() => {
-    const autogenerated = prefs?.autogenerated;
-    const theme =
-      typeof autogenerated === "object" && autogenerated !== null && !Array.isArray(autogenerated)
-        ? (autogenerated as Record<string, unknown>).theme
-        : null;
-    return typeof theme === "object" && theme !== null && !Array.isArray(theme)
-      ? (theme as Record<string, unknown>)
-      : null;
-  })();
+  const browserTheme = readNestedRecord(prefs?.browser, "theme");
+  const autogeneratedTheme = readNestedRecord(prefs?.autogenerated, "theme");
 
   const nameOk = typeof info?.name === "string" ? info.name === desiredName : true;
 
diff --git a/extensions/browser/src/browser/paths.ts b/extensions/browser/src/browser/paths.ts
index 2652161f1cc..135ac283c11 100644
--- a/extensions/browser/src/browser/paths.ts
+++ b/extensions/browser/src/browser/paths.ts
@@ -30,6 +30,12 @@ export const DEFAULT_DOWNLOAD_DIR = path.join(DEFAULT_BROWSER_TMP_DIR, "download
 export const DEFAULT_UPLOAD_DIR = path.join(DEFAULT_BROWSER_TMP_DIR, "uploads");
 
 type InvalidPathResult = { ok: false; error: string };
+type ResolvePathsWithinRootParams = {
+  rootDir: string;
+  requestedPaths: string[];
+  scopeLabel: string;
+};
+type ResolvePathsWithinRootResult = { ok: true; paths: string[] } | InvalidPathResult;
 
 function invalidPath(scopeLabel: string): InvalidPathResult {
   return {
@@ -146,11 +152,9 @@ export async function resolveWritablePathWithinRoot(params: {
   return lexical;
 }
 
-export function resolvePathsWithinRoot(params: {
-  rootDir: string;
-  requestedPaths: string[];
-  scopeLabel: string;
-}): { ok: true; paths: string[] } | { ok: false; error: string } {
+export function resolvePathsWithinRoot(
+  params: ResolvePathsWithinRootParams,
+): ResolvePathsWithinRootResult {
   const resolvedPaths: string[] = [];
   for (const raw of params.requestedPaths) {
     const pathResult = resolvePathWithinRoot({
@@ -166,34 +170,22 @@ export function resolvePathsWithinRoot(params: {
   return { ok: true, paths: resolvedPaths };
 }
 
-export async function resolveExistingPathsWithinRoot(params: {
-  rootDir: string;
-  requestedPaths: string[];
-  scopeLabel: string;
-}): Promise<{ ok: true; paths: string[] } | { ok: false; error: string }> {
-  return await resolveCheckedPathsWithinRoot({
-    ...params,
-    allowMissingFallback: true,
-  });
+export async function resolveExistingPathsWithinRoot(
+  params: ResolvePathsWithinRootParams,
+): Promise<ResolvePathsWithinRootResult> {
+  return await resolveCheckedPathsWithinRoot(params, true);
 }
 
-export async function resolveStrictExistingPathsWithinRoot(params: {
-  rootDir: string;
-  requestedPaths: string[];
-  scopeLabel: string;
-}): Promise<{ ok: true; paths: string[] } | { ok: false; error: string }> {
-  return await resolveCheckedPathsWithinRoot({
-    ...params,
-    allowMissingFallback: false,
-  });
+export async function resolveStrictExistingPathsWithinRoot(
+  params: ResolvePathsWithinRootParams,
+): Promise<ResolvePathsWithinRootResult> {
+  return await resolveCheckedPathsWithinRoot(params, false);
 }
 
-async function resolveCheckedPathsWithinRoot(params: {
-  rootDir: string;
-  requestedPaths: string[];
-  scopeLabel: string;
-  allowMissingFallback: boolean;
-}): Promise<{ ok: true; paths: string[] } | { ok: false; error: string }> {
+async function resolveCheckedPathsWithinRoot(
+  params: ResolvePathsWithinRootParams,
+  allowMissingFallback: boolean,
+): Promise<ResolvePathsWithinRootResult> {
   const rootDir = path.resolve(params.rootDir);
   // Keep historical behavior for missing roots and rely on openFileWithinRoot for final checks.
   const rootRealPath = await resolveRealPathIfExists(rootDir);
@@ -253,7 +245,7 @@ async function resolveCheckedPathsWithinRoot(params: {
       });
       resolvedPaths.push(opened.realPath);
     } catch (err) {
-      if (params.allowMissingFallback && err instanceof SafeOpenError && err.code === "not-found") {
+      if (allowMissingFallback && err instanceof SafeOpenError && err.code === "not-found") {
         // Preserve historical behavior for paths that do not exist yet.
         resolvedPaths.push(pathResult.fallbackPath);
         continue;