bug(mat-autocomplete): missing multiple option in mat-autocomplete, but in mat-select this feature present

[lopatnov]

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

Components are not consistent. They looks very close, but in mat-select you can choose multiple options, but in mat-autocomplete you don't have such opportunity. And I don't see any opportunity to prevent closing mat-autocomplete.

Reproduction

StackBlitz link: -
Steps to reproduce:

1. Create mat-autocomplete and mat-select with multiple option
2. mat-select has opportunity to select multiple items, but mat-autocomplete doesn't have this opportunity

Expected Behavior

mat-autocomplete should also have multiple options as in mat-select

Actual Behavior

mat-autocomplete doesn't react on multiple

Environment

• Angular:
  "@angular/cdk": "^19.2.15",
  "@angular/common": "^19.2.10",
  "@angular/compiler": "^19.2.10",
  "@angular/core": "^19.2.10",
• CDK/Material:
  "@angular/material": "^19.2.15",
• Browser(s): Chrome Version 136.0.7103.114 (Official Build) (64-bit)
• Operating System (e.g. Windows, macOS, Ubuntu): Windows 11

[crisbeto]

Duplicate of #5053.