vim mode in text file , the cursor is not correct for Chinese word

the cursor only cover half of the word , if it's a Chinese word , it should be like in vim in terminal

you can put this Chinese word for a test, '需求问题'
please check below two images

No file, test, or entry point is named in the issue. Reproduce the problem in a text file using vim mode and the Chinese sample “需求问题”, then compare cursor coverage with terminal Vim. Done means the cursor covers the full Chinese word rather than half of it.

Written by the indexing model from the issue text.