Symfony version(s) affected

Tested and reproduced on 4.4 and 5.3

Description

In case the first character of the string is ampersand &, then two equivalent syntax of YAML-Collections produce different output for the same values.

How to reproduce

Add YAML parameters like:

parameters:
    # Correct values in console output  -> ["&string1","&string2","&string3"]
    collection_output_correct:
        - '&string1'
        - "&string2"
        - !!str &string3

    # Wrong values in console output -> ["","","",""]
    collection_output_wrong: ['&string1', "&string2", !!str &string3, &string4 ]

Run bin/console debug:container --parameters and compare output for 'collection_output_correct' and 'collection_output_wrong' parameters.

Possible Solution

No response

Additional Context

No response