Adobe Support Request: Regression in Shared Review WebDAV Registration (Collab.registerReview())

Summary

We are a document management system vendor  and have integrated Adobe Acrobat/Reader’s legacy Shared Review functionality for many years. Our integration collects PDF annotations server-side using WebDAV.

Generated PDFs contain document-level JavaScript that registers the document for review:

Collab.registerReview({
    source: "<our WebDAV review folder URL>",
    driver: "urn://ns.adobe.com/Collaboration/SharedReview/WebDAV"
    // Additional review metadata omitted
});

javascript

When successful, this displays Acrobat/Reader’s built-in review toolbar and synchronizes comments with our WebDAV server.

Regression

The integration worked correctly with:

• Adobe Acrobat Reader DC 21662, 64-bit
• Adobe Acrobat Reader 26.1.21691

It stopped working after updating to:

• Adobe Acrobat Reader 2026.001.21771

With the affected build, the Shared Review toolbar does not appear and the review registration fails.

We reproduced the issue using a minimal isolated test PDF containing only an OpenAction that calls Collab.registerReview(). This rules out issues related to our document-generation pipeline.

Error

With Acrobat’s JavaScript debugger/console enabled, Reader reports:

NotAllowedError: Sicherheitseinstellungen verhindern den Zugriff auf diese Eigenschaft oder Methode.
Collab.registerReview:22:Doc undefined:Open

text

A screenshot of the error is attached separately.

Troubleshooting Performed

We have verified the following:

• Acrobat JavaScript is enabled.
• Protected Mode and Protected View were disabled for testing.
• Our domain and relevant paths were added to Acrobat’s trusted/privileged locations.
• These trust and URL configuration changes did not resolve the issue.
• Network capture shows no outbound WebDAV or HTTP traffic when the failure occurs.

The absence of network traffic suggests that the call is being blocked internally by Acrobat before any WebDAV connection is attempted.

Isolated Workaround and Findings

As a diagnostic step, we compared the complete installation folders of the last known-working build and the affected build.

Replacing only:

Acrobat\plug_ins\Annots.api

text

in the affected installation with the corresponding file from the working build—version 26.1.21691.0—restores both:

• The Shared Review toolbar
• Successful execution of Collab.registerReview()

No other files were changed.

This strongly indicates that the regression is isolated to the Annots.api component rather than our configuration, trust settings, document generation, or WebDAV service.

This binary replacement is strictly an internal diagnostic workaround and is not suitable for customer deployment. It involves mixing binaries from different Acrobat releases and may introduce compatibility, security, or stability issues. It also cannot be maintained across future updates or address the underlying defect in the shipped component.

Questions

Could Adobe please clarify the following?

1. Has Collab.registerReview() or the legacy Shared Review WebDAV driver been intentionally disabled, restricted, or removed in recent Acrobat/Reader Continuous-track releases?
2. If so, is there a supported policy or configuration that can re-enable this functionality?
3. If Shared Review has been retired, can Adobe confirm this and provide the relevant documentation or recommended migration path to a supported alternative?
4. Given that reverting only Annots.api restores the functionality, can Adobe confirm whether this regression is already tracked internally?
5. Is a corrected Annots.api or full patch release planned?

We would appreciate confirmation of the root cause and guidance on a supported solution, as we cannot rely on the current binary-replacement workaround for customer environments.

Release-Notes Check

We were unable to find any mention of this change in the published Acrobat/Reader release notes.