Hyper does not highlight underscores

[Django-B]

• I am on the latest Hyper.app version
• I have searched the issues of this repo and believe that this is not a duplicate

• OS version and name: Linux hp 5.10.0-kali3-amd64 SMP Debian 5.10.13-1kali1 (2021-02-08) x86_64 GNU/Linux

• Hyper.app version: 3.4.1

• Link of a Gist with the contents of your hyper.json: .hyper.js

• The issue is reproducible in vanilla Hyper.app: Is Vanilla

Issue

When I highlight text with the mouse cursor in the terminal or the text is highlighted in Neovim, Hyper does not highlight the underscore and the character following it.
Terminal example

Neovim example