I recently tried out version4.0.8. Mainly for the reason that SASS files are supported (i.e. you can directly importscss files in yourtsx files).

It works pretty well in the good browsers.

However it looks like the support (polyfills I guess) for IE (11) is gone, because in IE I now get this error:
Unhandled promise rejection ReferenceError: 'fetch' is undefined.
(which is to be expected because fetch API isn't supported by IE out of the box).

When upgradingreact-scripts-ts it also added a defaultbrowserslist to mypackage.json:

  "browserslist": [    ">0.2%",    "not dead",    "not ie <= 11",    "not op_mini all"  ]

According to this list it's clear for me that IE 11 is not supported anymore.

So I tried to modify the list like this (or even remove it entirely), in the hope that it then will add more polyfills or whatsoever:

  "browserslist": [    "defaults",    "not dead",    "not ie <= 10"  ]

However the behavior is unchanged.

Now before I invest more time in this, I wanted to ask a simple question:

Will version >= 4.0.8 not support Internet Explorer anymore, is this a bug or simply my own mistake?