Blazor WebAssembly in .NET 10 does not cache boot resources in browser Cache Storage, relies solely on HTTP cache instead

[arun442001]

Description

We are upgrading a Blazor WebAssembly application from .NET 8 to .NET 10. The application relies heavily on fast subsequent loads using the browser's Cache Storage API for .NET runtime files, assemblies (.dll), and WebAssembly files (.wasm).

In .NET 8 (and .NET 9), after the initial load, these resources are cached in the browser's Cache Storage (visible under Application > Cache Storage in Chrome DevTools), resulting in very fast reloads with minimal network traffic.
In .NET 10 , the Cache Storage remains empty for Blazor boot resources. Instead, caching appears to depend entirely on standard browser HTTP cache (visible under Network tab as "(from disk cache)" or "(from memory cache)").

We would like to restore the previous behavior where Blazor proactively caches boot resources in Cache Storage, independent of or in addition to HTTP caching.

In Net 10.0:

In Net 8.0:

[MihuBot]

I'm a bot. Here are possible related and/or duplicate issues (I may be wrong):

• Blazor WASM doesn't use cache after upadate from net9.0 to net10.0 #63682
• Blazor WASM doesn't use cache after upadate from net9.0 to net10.0 #63717

[javiercn]

@arun442001 thanks for contacting us.

This was an issue that we've recently patched. A fix for this will be available in the January servicing release.

Dupe of #64009