Steps to reproduce

1.  Disable receivers https://demo.magnolia-cms.com/.magnolia/admincentral#app:configuration:browser;/modules/publishing-core/config/receivers/magnoliaPublic8080@enabled:treeview:
2.  Delete a page https://demo.magnolia-cms.com/.magnolia/admincentral#app:pages-app:browser;/sportstation::

Expected results

Page is deleted and success message is shown.

Actual results

Page is deleted and exception is thrown.

Workaround

Use default variant aware column definition (if amount of pages is not huge and you are not affected with performance issue MGNLPN-560)

Development notes

Deletion trigger observation which rerenders the grid asynchronously (without a webcontext/request).
CachingVariantAwareTitleColumnDefinition fails to access request.
Checks if a simple check for null doesn't introduce a performance problem again for asynchronous requests.
Can we cache in ValueProvider and flush if mgnl:variant is added (via observation)?