[m-rev.] for review: fix singleton warnings for code with explicit quantification

[Zoltan Somogyi]

On 2023-06-09 19:50 +02:00 CEST, "Zoltan Somogyi" <zoltan.somogyi at runbox.com> wrote:
> For review by anyone.

In the absence of a review by then, I intend to commit this
in about six hours.

Zoltan.