jquery-ui.css: Illegal characters in path

[gulench]

Trying to create a CSS Bundle with jquery-ui.css fails with the following error:

System.ArgumentException: Illegal characters in path.
   at System.IO.PathHelper.Normalize(String path, Boolean checkInvalidCharacters, Boolean expandShortPaths)
   at System.IO.Path.GetFullPath(String path)
   at System.IO.FileInfo.Init(String fileName)
   at System.IO.FileInfo..ctor(String fileName)
   at WebOptimizer.CssFingerprinter.Adjust(String content, IFileInfo input, IFileInfo output, IHostingEnvironment env)
   at WebOptimizer.CssFingerprinter.ExecuteAsync(IAssetContext config)
   at WebOptimizer.Asset.<ExecuteAsync>d__22.MoveNext()
--- End of stack trace from previous location where exception was thrown ---
   at System.Runtime.ExceptionServices.ExceptionDispatchInfo.Throw()
   at System.Runtime.CompilerServices.TaskAwaiter.HandleNonSuccessAndDebuggerNotification(Task task)
   at WebOptimizer.AssetBuilder.<BuildAsync>d__5.MoveNext()
--- End of stack trace from previous location where exception was thrown ---
   at System.Runtime.ExceptionServices.ExceptionDispatchInfo.Throw()
   at System.Runtime.CompilerServices.TaskAwaiter.HandleNonSuccessAndDebuggerNotification(Task task)
   at WebOptimizer.AssetMiddleware.<HandleAssetAsync>d__6.MoveNext()
--- End of stack trace from previous location where exception was thrown ---
   at System.Runtime.ExceptionServices.ExceptionDispatchInfo.Throw()
   at System.Runtime.CompilerServices.TaskAwaiter.HandleNonSuccessAndDebuggerNotification(Task task)
   at Microsoft.AspNetCore.ResponseCompression.ResponseCompressionMiddleware.<Invoke>d__3.MoveNext()
--- End of stack trace from previous location where exception was thrown ---
   at System.Runtime.ExceptionServices.ExceptionDispatchInfo.Throw()
   at System.Runtime.CompilerServices.TaskAwaiter.HandleNonSuccessAndDebuggerNotification(Task task)
   at Microsoft.AspNetCore.Diagnostics.DeveloperExceptionPageMiddleware.<Invoke>d__7.MoveNext()

I suspect it is the content within comments at the top of the file that is causing the error:

...
* To view and modify this theme, visit http://jqueryui.com/themeroller/?ffDefault=Arial%2CHelvetica%2Csans-serif&fsDefault=1em&fwDefault=normal&cornerRadius=3px&bgColorHeader=e9e9e9&bgTextureHeader=flat&borderColorHeader=dddddd&fcHeader=333333&iconColorHeader=444444&bgColorContent=ffffff&bgTextureContent=flat&borderColorContent=dddddd&fcContent=333333&iconColorContent=444444&bgColorDefault=f6f6f6&bgTextureDefault=flat&borderColorDefault=c5c5c5&fcDefault=454545&iconColorDefault=777777&bgColorHover=ededed&bgTextureHover=flat&borderColorHover=cccccc&fcHover=2b2b2b&iconColorHover=555555&bgColorActive=007fff&bgTextureActive=flat&borderColorActive=003eff&fcActive=ffffff&iconColorActive=ffffff&bgColorHighlight=fffa90&bgTextureHighlight=flat&borderColorHighlight=dad55e&fcHighlight=777620&iconColorHighlight=777620&bgColorError=fddfdf&bgTextureError=flat&borderColorError=f1a899&fcError=5f3f3f&iconColorError=cc0000&bgColorOverlay=aaaaaa&bgTextureOverlay=flat&bgImgOpacityOverlay=0&opacityOverlay=30&bgColorShadow=666666&bgTextureShadow=flat&bgImgOpacityShadow=0&opacityShadow=30&thicknessShadow=5px&offsetTopShadow=0px&offsetLeftShadow=0px&cornerRadiusShadow=8px
...

[gulench]

This is an issue only on Windows; it works fine on Linux

[gulench]

This issue is no longer there with the ASP.Net Core 2.1 update.