Currently RESTBase has 2 ways of storing the HTML:
- The latest render of the latest revision is stored in the latest storage and updated via ChangeProp
- When VE requests a non-latest revision edit, Parsoid data is temporary stashed into a stashing table.
Currently, the resource_change event is emitted for both cases, picked up by ChangeProp and a rerender of Parsoid-dependent content like mobile-sections and summary is initiated. We do not need to initiate the rerender in the second case - it will basically be a no-op since we only render dependent content for the latest revision.
Although, we still need to purge Varnish for previous revision of Parsoid HTML that's being rerendered, so we still need to issue a resource_change for the URI with a revision - that will stop ChangeProp from rerendering the dependent content, but will preserve Varnish purging.