Andriod TalkBack reads background content when Offcanvas is open on Android

[LouisKoXiang]

Prerequisites

• I have searched for duplicate or closed issues
• I have validated any HTML to avoid common problems
• I have read the contributing guidelines

Describe the issue

When using the Bootstrap Offcanvas component on Android devices with TalkBack enabled, the screen reader can still navigate and read content outside of the Offcanvas dialog, even though aria-modal="true" is set. This behavior is inconsistent with expected accessibility standards and contrasts with iOS VoiceOver, which correctly limits navigation to the Offcanvas component.

Steps to Reproduce

1. Open an Offcanvas component on a web page.
2. Enable TalkBack on an Android device.
3. Swipe or navigate using TalkBack gestures.
4. Observe that TalkBack can still read content outside of the Offcanvas dialog.

Expected Behavior
When aria-modal="true" is set on the Offcanvas component:

TalkBack should restrict focus and navigation to the Offcanvas dialog.
Background content should not be navigable or readable by TalkBack, aligning with the expected behavior described in the ARIA specification.

Reduced test cases

https://getbootstrap.com/docs/5.0/components/offcanvas/ test

What operating system(s) are you seeing the problem on?

Android

What browser(s) are you seeing the problem on?

Chrome

What version of Bootstrap are you using?

online