trouble regarding 'addon_updater_install_popup'

[Raccoon-JS]

I received this error when I tried to add this addon.

Traceback (most recent call last):

  File "/usr/share/blender/scripts/modules/addon_utils.py/", line 382, in enable

    mod.register()

  File "home/<me>/.config/blender/2.82/scripts/addons/coa_tools/__init__.py", line 264. in register

    addon_updater_ops.register(bl_info)

  File "home/<me>/.config/blender/2.82/scripts/addons/coa_tools/addon_updater_ops.py", line 1086, in register

    bpy.utils.register_class(addon_updater_install_popup)

ValueError: register_class(...): already registered as a subclass 'addon_updater_install_popup'