上传文件假死 The program will be unresponsive for more than 10 seconds when dragging and dropping files to upload

ver 2.7.0
版本 2.7.0

The program will be unresponsive for more than 10 seconds when dragging and dropping files to upload
拖放文件上传时，程序将无响应（假死）超过 10 秒

I don't know what caused it, I tried many ways but still can't solve it
不知道是什么原因造成的，试了很多方法还是没能解决

The issue names no source files, tests, or entry points. Reproduce the problem on version 2.7.0 by dragging and dropping files to upload, then trace the upload path to identify what blocks the program; done means the program remains responsive during the operation and no longer hangs for more than 10 seconds.

Written by the indexing model from the issue text.