pkg wants to install perl5.24 even thought it's not required

[Serpent7776]

Hello,

I have strange issue: when I install or upgrade a package pkg wants to install
perl5.24 too every time. That's strange because all ports require perl5.26, not
perl5.24.
After installation/upgrade when I do pkg autoremove pkg tells that
perl5.24 in not required and can be deleted.
I have not specified any default perl version in /etc/make.conf.
I'm using custom built ports via poudriere.
What might be causing this?

Thanks
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