Reuse the previous route instance

[fantasia949]

In my scenario, I have an index route that displays item list, and a detail route to show detail info for each item. The content of the index route is rarely changed, but I have to pay a cost (~100ms) to make it visible. Each time I view the content of the detail route, then navigate back to the index route, the transition is not quite smooth. Looking at the performance timeline, I notice the index route instance is destroyed and reconstructed again for each roundtrip, so it's not effective, especially when that route contains a bunch of child components. Is there any possible way to make the router be able to cache the prev route instance, and then reuse it again when user navigates back?

[developit]

This is how preact worked in previous versions, but there are too many issues arising from caching DOM - most importantly, it's quite bad for memory management (images & videos never getting GC'd, etc).