Blazor WebAssembly fingerprint not replaced on publish

[vsfeedback]

This issue has been moved from a ticket on Developer Community.

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In a Hosted Blazor WebAssembly app, publishing from the Server project fails to replace the #[.{fingerprint}] token in index.html, resulting in a 404 error for blazor.webassembly.js."

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Original Comments

Feedback Bot on 2/27/2026, 09:29 AM:

We have directed your feedback to the appropriate engineering team for further evaluation. The team will review the feedback and notify you about the next steps.

[MihuBot]

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

• Fingerprinting client-side assets using the old school hosted approach runtime#121993
• Blazor WebAssembly: Placeholder in index.html not replaced after publish in hosted configuration (.NET 10 RC2) #64199
• OverrideHtmlAssetPlaceholders is not honored when building from Server project runtime#121121
• Blazor WebAssembly fingerprint not applied in certain publish scenarios #64543

[oroztocil]

Hi, can you provide more details about your setup and the commands that you are running?

[rogihee]

Having a similar issue. From one machine it refuses to give correct fingerprint, even after nukin bin/obj and .nuget cache. Always same fingerprint after publish on server that then triggers 404s, while in console it looks ok (fresh fingerprint every build). Other machine it worked ok, both are on 10.0.103 SDK and 18.2.3 VS2026

[oroztocil]

@rogihee If I understand it correctly, your issue is a bit different: You get an incorrect fingerprint (in some cases), while the original issue reports the fingerprint not getting replaced at all.

If you keep running into the problem, please file a separate issue and include your project configuration and if possible a binlog from the build(s). Thanks!

[oroztocil]

To the original reporter: To investigate your case, we need more info about your project configuration. Can you also provide us with a binlog from the faulty build?

See https://github.com/dotnet/msbuild/blob/main/documentation/wiki/Providing-Binary-Logs.md

[dotnet-policy-service]

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[dotnet-policy-service]

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