Bootstrap class: .form-text

    <label for="inputPassword5" class="form-label">Password</label>
    <input type="password" id="inputPassword" class="form-control" aria-describedby="passwordInfo">
    <div id="passwordInfo" class="form-text">
    Your password must be 8-15 characters long, and this is an example of form-text
    </div>

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Your password must be 8-15 characters long, and this is an example of form-text

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