render issue：part of glyph missing if you mix non-ASCII and ASCII characters

[jdhao]

I am using fvim on Windows 10.

Steps to reproduce:

• Open fvim with command to edit an empty file: fvim -u NORC test.md
• Go to insert mode, type 我, followed by space. Then turn off IME and input a ASCII character (it does not matter which character you input).

Now, you will notice that part of the character 我 is missing. But if you go to normal mode and put the cursor in character 我, it is shown completely.

I also tried nvim-qt. It doesn't exhibit this behavior.

[yatli]

Can repro. Thanks for noting!