[a11y] The content behind the in-product help sheets is narrated when keys other than the “Tab” key are used

[data-sync-user]

Important details: 

• reproducing for the In-product help sheets from other screens as well (Privacy features, DNS, App exclusions, My devices); 

• not reproducing if navigating with the “Tab” key after the in-product help sheet is displayed;

• reproducing on Windows 10/11 as well if navigating backwards using “Caps” + “U” keys after reaching the end of the In-product help sheet;

Version / build found in: 

• 2.21.0 (2.202402070521)

Reproducible on:

• MacOS 12.6.6;

Prerequisites:

• Have Mozilla VPN app installed and open;

• Have a Mozilla account with an active subscription;

• Be signed in;

• Have the “Help sheets” option from Features list enabled;

• Have the Screen Reader enabled;

Steps to reproduce:

1. Go to Select location and open the In-product help sheet;
2. Navigate through the screen while using the right arrow;
3. Observe the behavior;

Expected result:

• Only the content from the in-product help sheet is narrated by the Screen Reader;

Actual result:

• The content behind the in-product help sheet is narrated by the Screen Reader (nav bar, servers list). The in-product help sheet does not gain focus;

Notes:

• See the attached video;

┆Issue is synchronized with this Jira Bug ┆Reporter: Bianca Hidecuti

[data-sync-user]

➤ Raluca Monica Ilban commented:

The issue also is reproducible for "Confirm reset" modal, while using 2.21.0 (2.202402122056) build on MacOS 12.6.6/Win 10.

MacOS: Open the Confirm reset modal and navigate using the left/right arrows.

Win: Press the Tab key until the "X" gets focus, then navigate using CAPS+U keys.

The content behind the modal is read.