Don't show toolbar when rendering within GitBook app preview

[viktorrenkema]

When a preview link for a change-request or revision is opened, we show a toolbar with helpful info and actions. However, we don't want to show this toolbar if the site is rendered in an iframe in the GitBook web-app editor, under the preview tab.

This behaviour likely broke when the 'multi-id' functionality became obsolete with the move to gbo v2.

• this pr removes that old logic
• and replaces it with a new check using the existing isPreviewRequest util

Examples

Toolbar no longer shows when previewing in-app:

Toolbar still shows when visiting a change-request or revision preview link:

[linear]

RND-7992 Hide/disable preview pill when displayed in an iframe in the app

[changeset-bot]

⚠️ No Changeset found

Latest commit: 16bf6b9

Merging this PR will not cause a version bump for any packages. If these changes should not result in a new version, you're good to go. If these changes should result in a version bump, you need to add a changeset.

This PR includes no changesets

When changesets are added to this PR, you'll see the packages that this PR includes changesets for and the associated semver types

Click here to learn what changesets are, and how to add one.

Click here if you're a maintainer who wants to add a changeset to this PR

[github-actions]

Summary of the deployments:

Version	URL	Status
Vercel	https://gitbook-v2-hhk2y3uim-gitbook.vercel.app	✅
Cloudflare	https://378cf391-gitbook-open-v2-preview.gitbook.workers.dev	✅

Test content

Site	2v	2c
GitBook	https://gitbook-v2-hhk2y3uim-gitbook.vercel.app/url/gitbook.com/docs	https://378cf391-gitbook-open-v2-preview.gitbook.workers.dev/url/gitbook.com/docs
E2E	https://gitbook-v2-hhk2y3uim-gitbook.vercel.app/url/gitbook.gitbook.io/test-gitbook-open	https://378cf391-gitbook-open-v2-preview.gitbook.workers.dev/url/gitbook.gitbook.io/test-gitbook-open

[argos-ci]

The latest updates on your projects. Learn more about Argos notifications ↗︎

Build	Status	Details	Updated (UTC)
customers-v2 (Inspect)	⚠️ Changes detected (Review)	9 changed	Sep 9, 2025, 12:56 PM
v2-cloudflare (Inspect)	👍 Changes approved	4 changed	Sep 9, 2025, 12:59 PM
v2-vercel (Inspect)	👍 Changes approved	1 changed	Sep 9, 2025, 12:58 PM

[gregberge]

I think we should do this only on iframe, if we decide to be able to open the preview in a new tab later it will break.