This issue was raised in the somewhat related ticket, JRACLOUD-76643 – Default image attachment size as thumbnail.

Use case 1:
We are using the Forms feature in Jira Service Management. Once a form is submitted, it gets attached to the ticket as a PDF.

However, we have noticed that when viewing the attached PDF within the Jira agent view, it automatically zooms in between 300-400%. This behaviour seems unnecessary, default zoom level should be 100%-125% maximum. This way, if the form is not too long, all the content can be conveniently displayed on a single page.

Currently users have to locate the zoom out button as the first step when opening the PDF.