use multipart/form-data for the first time No Content
the second time
before, I also thought it was caused by the component. The back end said that Access-Control-Allow-Headers is not the default request, so the request is not a simple request, like this 
graphqlfetchheader 
Why did it happen twice?
We never met. There must be something wrong with the
parameter.
additional requests can be sent to Filter if it is favicon.ico.
backend settings Access-Control-Allow-Headers plus Authorization,X-Requested-With
these two headers are required for uploading a file request
and you can upload normally
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