bug(mat-autocomplete): doesn't allow to have an overlay backdrop

[6apc1k]

Is this a regression?

• Yes, this behavior used to work in the previous version

The previous version in which this bug was not present was

No response

Description

Currently, autocomplete component lacks the ability to display a backdrop overlay, which makes it's behaviour inconsistent with other components that have overlay (mat-select, mat-menu, etc.).

It might be useful to create a transparent backdrop to block the interactions with the background until the panel is closed (especially when using it in combination with mat-chip-grid), and to be able to make its behaviour consistent with other components such as mat-select.

Reproduction

Steps to reproduce:

https://material.angular.io/components/autocomplete/examples

1. Open panel in mat autocomplete
2. Hover over other elements on the page
3. Observe hover events are not being blocked by a backdrop

Expected Behavior

mat-autocomplete offers a configuration option (e.g. hasBackdrop) to enable or disable the backdrop.

Actual Behavior

There's no way to to create an overlay backdrop with mat-autocomlete.

Environment

• Angular: 19.0.5
• CDK/Material: 19.0.5
• Browser(s): Chrome
• Operating System (e.g. Windows, macOS, Ubuntu): MacOS

[mDjeee]

same issue, fix please!