The release note in English is very concise. And for v1.0.4, I fixed several bugs related to Chinese input method and those pull requests have been contributed back to GNU TeXmacs. These improvements are not available in v2.1.2. If you are using Input Method (CJK or others), Mogan Editor is worth a try.
And for Windows and macOS, I bundled the Eukleides binary. I think it would be helpful for education purpose.