### Problem to solve We currently need to click on *Changes* tab to see how many actual changes a MR is sending. What if we presented it right in the main MR page? ### Further details Just to illustrate the idea:  ### Proposal In a backend perspective, fetching diff statistics now consumes less memory and it's [_much_ faster](https://dashboards.gitlab.net/d/U50nQ9Smk/gitaly-endpoint-times-host-vs-fleet-average?orgId=1&var-grpc_method=DiffStats&var-fqdn=file-04-stor-gprd.c.gitlab-production.internal) and reliable. Therefore we can leverage that to give this information for "free" to the users upfront. ### What does success look like, and how can we measure that? - Diff statistics being presented in the main page (no need to enter *Changes* tab for having an idea of the diff size). - Git timings stay low on [`Projects::MergeRequestsController#show`](https://dashboards.gitlab.net/d/thYzurImk/rails-controllers?orgId=1&var-action=Projects::MergeRequestsController%23show&var-database=influxdb-01-inf-gprd). ### Links / references