What is this vim plug-in? how to remove

Question

Plug-in with vertical bar.

Answer 1

is not a plug-in, it is a configuration. Remove set cursorcolumn 就好了，或者设置 set nocursorcolumn in .vimrc to overwrite the previous settings.

Answer 2

For example, if your project has requirements and is controlled at 80 or 120 columns, this vertical line will serve as a reminder.
Refer to the method above

Answer 3

This is vim’s block operation