Chinese IME fails on Microsoft Edge

[J22Melody]

I know some known IME issues such as #854 and I can solve them by patch PRs like #1107 and #880, but in Microsoft Edge, Chinese IMEs like Microsoft Pinyin still behave wierd.

Here is my example in Slate 0.25.0 Microsoft Edge 20 Windows 10 with Microsoft Pinyin:

I'm not sure if it is related or it's another issue only appears in Microsoft Edge. Does anyone encounter the same problem. Any workaround?

By the way, slatejs.org does not work in Microsoft Edge, which is already mentioned in #1186.