Failed to load the css-edit-groups package

[Enter steps to reproduce:]

1. ...
2. ...

Atom: 1.37.0 x64
Electron: 2.0.18
OS: Microsoft Windows 10 Home
Thrown From: css-edit-groups package 0.4.2

Stack Trace

Failed to load the css-edit-groups package

At Duplicate key 'cmd-l'

Error: Duplicate key 'cmd-l'
    at Object.r (<embedded>:11:582198)
    at addProperty (<embedded>:14:1910662)
    at Array.reduce (<anonymous>:null:null)
    at Obj (<embedded>:14:1910328)
    at transformNode (<embedded>:14:1911702)
    at Value (<embedded>:14:1909576)
    at transformNode (<embedded>:14:1911702)
    at addProperty (<embedded>:14:1910650)
    at Array.reduce (<anonymous>:null:null)
    at Obj (<embedded>:14:1910328)
    at transformNode (<embedded>:14:1911702)
    at Value (<embedded>:14:1909576)
    at transformNode (<embedded>:14:1911702)
    at Block (<embedded>:14:1909534)
    at transformNode (<embedded>:14:1911702)
    at Object.parse (<embedded>:14:1911723)
    at m (<embedded>:11:579441)
    at c (<embedded>:11:579647)
    at Object.readFileSync (<embedded>:11:580740)
    at keymaps.getKeymapPaths.map.e (<embedded>:11:3543291)
    at Array.map (<anonymous>:null:null)
    at Package.loadKeymaps (<embedded>:11:3543279)
    at measure (<embedded>:11:3536833)
    at Package.measure (<embedded>:11:3536028)
    at Package.load (<embedded>:11:3536769)
    at PackageManager.loadAvailablePackage (<embedded>:11:381204)
    at config.transact (<embedded>:11:379627)
    at Config.transact (<embedded>:11:332146)
    at PackageManager.loadPackages (<embedded>:11:379565)
    at t.loadState.then (<embedded>:1:708589)
    at <anonymous>:null:null

Commands

Non-Core Packages

atom-autocomplete-python 5.0.0 
atom-emmet-css-in-js 0.2.0 
atom-icons 0.2.2 
atom-import-js 0.21.0 
atom-js 1.2.0 
atom-js-console 1.2.2 
atom-live-server 2.3.0 
atom-live-server-plus 3.0.1 
atom-material-ui 2.1.3 
atom-python-run 0.9.7 
atom-python-virtualenv 1.0.2 
autocomplete-python 1.14.0 
awesome-python-snippets 0.3.0 
build 0.70.0 
build-python 0.9.3 
busy-signal 2.0.1 
css-edit-groups 0.4.2 
css-grid-snippets 1.1.1 
css-helper-snippets 0.3.0 
css-in-js 1.4.0 
css-spy 0.6.0 
emmet 2.4.3 
emmet-jsx-css-modules 1.0.0 
firacode 0.3.0 
fonts 3.4.0 
html-to-css 0.2.2 
html-to-jsx 2.0.3 
Hydrogen 2.9.0 
icon-fonts 3.1.5 
icon-fonts-legacy 2.7.0 
ide-python 1.4.1 
kite 0.161.0 
letter-spacing 0.3.2 
live-reload-sass 0.1.0 
minimap 4.29.9 
minimap-lens 0.2.0 
python-debugger 0.2.0 
python-indent 1.2.3 
python-requirements 0.2.1 
python-snippets 1.9.0 
python-suite 0.3.2 
python-tools 0.6.9 
teletype 0.13.4 
Webfont 1.1.0 

Start by reproducing the failure with css-edit-groups 0.4.2 in Atom 1.37.0 on Windows 10, then inspect the package's keymap definitions for the duplicate cmd-l entry shown in the stack trace. Done means the package loads without the duplicate-key error.