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Currently, .NET 6 is still not fully supported in SF.
Checked with internal team on this, The GA support for .NET 6 is targeted for SF 9.0 release, the release date is not yet decided.
Support for IHost and IWebHost in AspNetCoreCommunicationListener is shipped in 5.2.1363, but the docs and samples are work in progress. Team is working on more framework support.
Similar ask here: https://learn.microsoft.com/en-us/answers/questions/636450/service-fabric-net-6-support.html
Hope that helps.
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