application/xhtml+xmlis not one of the built-in mime types that IIS compression knows for compression. You must enable compression for this mime type explicitly.
, , , . mime- system.webServer/httpCompression staticTypes dynamicTypes. script - appcmd.exe :
appcmd.exe set config -section:system.webServer/httpCompression /+"staticTypes.[mimeType='application/xhtml%%2bxml',enabled='True']" /commit:apphost
appcmd.exe set config -section:system.webServer/httpCompression /+"dynamicTypes.[mimeType='application/xhtml%%2bxml',enabled='True']" /commit:apphost
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