Thank you for the feedback! The PDF viewer was updated due to a security fix, which is why the behavior changed after upgrading.
We understand the missing zoom controls and page navigation panel have impacted your workflow. The team is aware of this and will continue to improve the new viewer !
Unfortunately there’s no option to switch back to the old viewer at this time. We appreciate your patience while the improvements are being worked on.
Due to security concerns, the PDF preview function has been replaced with pdf.js rendering, and it no longer functions exactly as before. However, file previews using third-party object storage remain the same. We recommend using object storage for attachments.