Failed to load the css-edit-groups package

[Enter steps to reproduce:]

1. ...
2. ...

Atom: 1.52.0 x64
Electron: 6.1.12
OS: macOS 11.0
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>:11:583386)
    at addProperty (<embedded>:14:1377736)
    at Array.reduce (<anonymous>:null:null)
    at Obj (<embedded>:14:1377402)
    at transformNode (<embedded>:14:1378776)
    at Value (<embedded>:14:1376650)
    at transformNode (<embedded>:14:1378776)
    at addProperty (<embedded>:14:1377724)
    at Array.reduce (<anonymous>:null:null)
    at Obj (<embedded>:14:1377402)
    at transformNode (<embedded>:14:1378776)
    at Value (<embedded>:14:1376650)
    at transformNode (<embedded>:14:1378776)
    at Block (<embedded>:14:1376608)
    at transformNode (<embedded>:14:1378776)
    at Object.parse (<embedded>:14:1378797)
    at m (<embedded>:11:580629)
    at c (<embedded>:11:580835)
    at Object.readFileSync (<embedded>:11:581928)
    at <embedded>:11:3191711
    at Array.map (<anonymous>:null:null)
    at Package.loadKeymaps (<embedded>:11:3191699)
    at <embedded>:11:3185153
    at Package.measure (<embedded>:11:3184316)
    at Package.load (<embedded>:11:3185089)
    at PackageManager.loadAvailablePackage (<embedded>:11:381794)
    at <embedded>:11:380217
    at Config.transact (<embedded>:11:332187)
    at PackageManager.loadPackages (<embedded>:11:380155)
    at <embedded>:1:716065
    at Function.all (<anonymous>:null:null)
    at AtomEnvironment.startEditorWindow (<embedded>:1:718104)

Commands

Non-Core Packages

atom-prettify 0.1.3 
codekit-atom-sync 1.0.0 
css-edit-groups 0.4.2 

Start by inspecting the css-edit-groups package's keymap definitions and the Atom Package.loadKeymaps path implicated by the stack trace. Reproduce on Atom 1.52.0 on macOS if possible, then verify that the package loads without the duplicate 'cmd-l' error.