How to delete/dismiss hundrets of stale persistent notifications?

I accidentally created hundreds of persistent notifications.
They are not accessible through the gui anymore but still show in devtools > states.

I can not list them with

{{ states.persistent_notification }}

or

{{ states|selectattr('state','eq','notifying') }}

How can I bulk-dismiss or delete them?

Have you tried restarting home assistant?

Yes, but for some reason they seem to be persistent :thinking:

Ups, just checked again. They are gone now. No idea what happened between my post and now. These entities were present for several days and through several reboots. Now they are gone.

Maybe just a display/cache problem.