Using diffs was our very first approach. It was quite naive (not to say dumb) solution but we also came to a conclusion that it will be problematic for tree-str

Using diffs was our very first approach. It was quite naive (not to say dumb) solution but we also came to a conclusion that it will be problematic for tree-structured data and there were also performance issues (for example when you bolded the whole document). So instead of trying to fix those issues, we tried a different approach.