Is your feature request related to a problem? Please describe.
I switched from single certs to wildcards and deleted all SSl Certs I thought not being used (I did not see the 'Active Domain Names' in the same menu (stupid me ;-) )
--> I forgot to change the certs the streams were using so after a restart npm did not start anymore

Describe the solution you'd like

Could you please prevent deleting a cert as long as it it actively in use?