BetterFountain stops the Vim extension from working

Describe the bug
When the BetterFountain extension is loaded when VSCode starts, the Vim extension no longer works at all.

I'm not sure if this is a bug on Vim or BetterFountain, and have submitted it to both. The issue on BetterFountain is https://github.com/piersdeseilligny/betterfountain/issues/51.

To Reproduce
Steps to reproduce the behavior:

1. Start vscode with BetterFountain and Vim enabled
2. Open a .fountain file
3. Push 'esc', 'i', 'abc'
4. 'iabc' is added to the document

Expected behavior
Vim would go into command mode, then insert mode, and then 'abc' would be added to the document.

Environment (please complete the following information):

• Extension (VsCodeVim) version: 1.12.4
• VSCode version: 1.14.1
• OS: Win 10 Pro 64bit (build 18362)

Additional context
If BetterFountain is disabled, then (as required), you reload Vscode, and then Enable BetterFountain, the Vim functionality works as well as the BetterFountain functionality

Start by reproducing the interaction with BetterFountain and VSCodeVim enabled at VSCode startup, following the listed steps in a .fountain file. Compare that behavior with the documented sequence where BetterFountain is enabled after reload; done means Vim reliably enters command and insert modes while BetterFountain remains enabled.