Composer's bash completion breaks Apt bash completion

Steps to reproduce:

On a fresh Debian install (with an empty /etc/bash_completion.d/ folder), check that apt completion works:

$ sudo apt install php<tab><tab>
Display all 2403 possibilities? (y or n)

Install Composer's bash completion script as described in $ composer help completion:

$ composer completion bash | sudo tee /etc/bash_completion.d/composer

Open a new shell and test both Composer's and Apt's autocompletion. The former works but the latter do not.

$ composer in<tab><tab>
info     init     install  
$ sudo apt install php<tab><tab>

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