problem solved.
I took the initiative to uglify the avalon, before introducing the project. At this time, I have no place to go. The bag typed by uglifyjs-webpack-plugin,webpack can be used under IE8. However, if you use uncompressed avalon, to decompress directly with webpack's uglifyjs-webpack-plugin, you will not be able to use it under IE8. I think there's something wrong with uglifyjs-webpack-plugin.