<?php if($board->viewUsernameField()):?>
<div class="kboard-attr-row">
    <label class="attr-name" for="kboard-input-member-display"><?php echo __('Author', 'kboard')?></label>
    <div class="attr-value"><input type="text" id="kboard-input-member-display" name="member_display" value="<?php echo $content->member_display?>" placeholder="<?php echo __('Author', 'kboard')?>..."></div>
</div>
<div class="kboard-attr-row">
    <label class="attr-name" for="kboard-input-password"><?php echo __('Password', 'kboard')?></label>
    <div class="attr-value"><input type="password" id="kboard-input-password" name="password" value="<?php echo $content->password?>" placeholder="<?php echo __('Password', 'kboard')?>..."></div>
</div>

위 코드를 찾아서

아래처럼 코드를 변경해주세요.

<div class="kboard-attr-row">
    <label class="attr-name" for="kboard-input-member-display"><?php echo __('Author', 'kboard')?></label>
    <div class="attr-value"><input type="text" id="kboard-input-member-display" name="member_display" value="<?php echo $content->member_display?>" placeholder="<?php echo __('Author', 'kboard')?>..."></div>
</div>
<?php if($board->viewUsernameField()):?>
<div class="kboard-attr-row">
    <label class="attr-name" for="kboard-input-password"><?php echo __('Password', 'kboard')?></label>
    <div class="attr-value"><input type="password" id="kboard-input-password" name="password" value="<?php echo $content->password?>" placeholder="<?php echo __('Password', 'kboard')?>..."></div>
</div>