No, there is no thread regarding username changes as updating username logs requires manual efforts.
However, since changing usernames is a software-based process now, you can click on any username to find their previous username. Once an username change request is approved, the previous username is visible till 60 days on the user profile.
Refer to the instructions provided on this thread to learn more:
Hello everyone, At times you may want to change your username for a specific reason, either to correct it or to set a proper username. Previously, you had to request a team member to change your username, but with this new update, you can change your username by yourself. However, a team...
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