Page delete hook error

I am using the page.delete:before hook. It was working fine, but now I’m running into problems. The hook does not seem to be getting called. If if do a simple dump I am getting a “this.$store is undefined” error.

If this is my only hook:

return [
    'page.delete:before' => function ($page) {

I get this error when trying to dump:

Any ideas what’s going on?