Issue

When navigating a modal dialog using the Tab key at 200% browser zoom or higher, keyboard focus moves out of the modal and lands on inactive elements in the background page. 

Symptoms and Impact 

Users who rely on keyboard navigation, including those using assistive technology, may lose context, encounter inaccessible elements, or be unable to complete tasks within the modal.  

This breaks the expected focus boundary of the modal and violates WCAG 2.1 Success Criterion 2.1.2 (No Keyboard Trap) and 2.4.3 (Focus Order).  

 The issue does not occur when navigating backward using Shift+Tab.  

Steps to reproduce 

1. Open a Pega application running on Pega Platform™ '25.1.3. 
2. Set browser zoom to 200% or higher. 
3. Open any modal dialog (for example, a table filter dialog). 
4. Press Tab repeatedly to navigate forward through the modal's interactive elements. 
   •  Result: Focus eventually moves behind the modal to elements on the background page. 
5.  Confirm the issue does not occur when pressing Shift+Tab to navigate backward. 

Root Cause

The modal dialog does not implement a focus boundary (focus trap). When the end of the modal's tab sequence is reached at high zoom levels, the browser's natural tab order continues onto elements rendered behind the modal, rather than cycling back to the first interactive element inside the modal. 

Solution

This issue is planned to be addressed in a future Pega Platform release.  

Issues are prioritized based on impact, severity, and capacity. The specific release for the fix has not yet been determined.  This section will be updated with release details when the fix for this issue is available.  

If keyboard accessibility compliance is a hard requirement before a patch is available, consider temporarily disabling or replacing the affected modal with an inline interaction pattern, or engaging your Pega account team to discuss options.