SPFX ListView Extension should also work in the list(preview) webpart
When adding the "List (preview)" web part to a modern page, i expect that ListView Extension do also work in this webpart.
Realted issue : https://github.com/SharePoint/sp-dev-docs/issues/2641
Peter Vincent commented
the view formatting with JSON looks good in the list but when you add the list as a webpart the JSON formatting looks bad