Issue Summary

There appears to be an issue with the modals on the JSM portal, where all modals open at the top of the window.

This problem affects modals created using both the Forge/React (Modal) and Forge/Bridge (Forge Bridge Modal) APIs. Despite one being a UI Kit and the other a Custom UI, there is no distinction in behavior; the issue persists across both implementations.

In other areas of Jira, the modal is properly displayed. The issue appears to be isolated to the customer portal, and it occurs consistently across different sections such as requests, profiles, and the request creation view.

Linked ticket
https://jira.atlassian.com/browse/ECO-921 

Upon investigation, it is suspected a JSM issue with design token variable fallbacks. A fix JSM could try is to configure CSS design token variables to not use the fallbacks. 

Steps to Reproduce

1. The easiest way to reproduce this is to create a simple hello world forge app with the jiraServiceManagement:portalUserMenuAction module
2. Or create a new JSM app, using UI Kit and add use a modal that will appear inside the Customer Portal

Expected Results

App modals in JSM - Customer Portal should have the same styling and behaviour as other modals in Jira view or by core JSM

Actual Results

Modals in JSM open at the top of the window with no padding which disrupts the user experience and does not have the same behaviour in Jira. 

Workaround

Currently there is no known workaround for this behavior. A workaround will be added here when available