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The goal is to guarantee that authenticated users always receive up‑to‑date dynamic page cache content without requiring site builders to manually add the 'user' cache context.

This raises constraints around potential performance overhead, backward compatibility for existing sites that rely on custom cache contexts, and the pending core decision about whether such enforcement should be automatic.

Because the core has not yet decided to enforce automatic cache context variation for authenticated users when using dynamic page caches, it remains unclear whether the benefit of guaranteed freshness outweighs the possible impact on cache hit rates and resource consumption.

Should Drupal core automatically apply the 'user' cache context to dynamic page cache for authenticated users?
What performance trade‑offs would arise from enforcing this context variation on high‑traffic sites?
How would this change affect existing implementations that already manage cache contexts customly?