Adopt a more lazy approach to read tex content
Adopt a more lazy approach to read tex content

This is a follow-up on
https://github.com/James-Yu/LaTeX-Workshop/issues/2671#issuecomment-835562749

James-Yu/LaTeX-Workshop,James-Yu/LaTeX-Workshop,James-Yu/LaTeX-Workshop,James-Yu/LaTeX-Workshop,James-Yu/LaTeX-Workshop