fix(security): lowercase-normalize COOKIE_DOMAIN before validation (follow-up #190)

[Jose-Gael-Cruz-Lopez]

Queued nit from the cross-PR review. sanitizeCookieDomain's regex is lowercase-only, so a valid config like .SaplingLearn.com was rejected and silently degraded to a host-only cookie. DNS is case-insensitive — .toLowerCase() the input before validating. Test covers normalization.

⚠️ Nit, do not merge without your review (queued per your instruction).

[coderabbitai]

Warning

Review limit reached

@Jose-Gael-Cruz-Lopez, we couldn't start this review because you've reached your PR review rate limit.

More reviews will be available in 58 minutes and 35 seconds. Learn how PR review limits work.

Your organization has used up its prepaid credits, and credit purchases are no longer available. Enable the review add-on in the billing tab to keep reviews running — you're only billed for reviews past your plan's rate limits ($0.25/file).

⌛ How to resolve this issue?

After more reviews become available, a review can be triggered using the @coderabbitai review command as a PR comment. Alternatively, push new commits to this PR.

We recommend that you space out your commits to avoid hitting the rate limit.

🚦 How do rate limits work?

CodeRabbit enforces hourly rate limits for each developer per organization.

Our paid plans include higher PR review limits than trial, open-source, and free plans. In all cases, reviews become available again over time. During sustained high-volume PR review activity, CodeRabbit may temporarily slow when the next review becomes available.

Please see our Fair Usage Limits Policy for further information.

ℹ️ Review info

⚙️ Run configuration

Configuration used: defaults

Review profile: CHILL

Plan: Pro Plus

Run ID: 72513d53-5af5-4dab-8cc5-06cbcb58b511

📥 Commits

Reviewing files that changed from the base of the PR and between 84aee68 and 0a74e75.

📒 Files selected for processing (2)

• frontend/src/lib/cookieDomain.test.ts
• frontend/src/lib/cookieDomain.ts

✨ Finishing Touches

🧪 Generate unit tests (beta)

• Create PR with unit tests
• Commit unit tests in branch security/follow-up-221-cookie-domain-lowercase

---

Thanks for using CodeRabbit! It's free for OSS, and your support helps us grow. If you like it, consider giving us a shout-out.

❤️ Share

• X
• Mastodon
• Reddit
• LinkedIn

_{Comment @coderabbitai help to get the list of available commands and usage tips.}

[cloudflare-workers-and-pages]

Deploying with    Cloudflare Workers

The latest updates on your project. Learn more about integrating Git with Workers.

Status	Name	Latest Commit	Preview URL	Updated (UTC)
✅ Deployment successful! View logs	frontend	0a74e75	Commit Preview URL Branch Preview URL	Jun 14 2026, 03:37 AM