Edit Accounts permission is not visible while other edit permissions are there like edit extension.
Where can they be found?
'Edit Accounts Permission' is advanced permission and can be added only after you submit a support ticket to the developer support team.
ref:
Using the RingCentral Phone for Desktop, you can dial or receive test calls, send and receive test SMS or Fax messages in your sandbox environment.
Download RingCentral Phone for Desktop:
Tip: switch to the "sandbox mode" before logging in the app:
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