zulip/static/templates/settings/settings_checkbox.hbs

{{#unless (eq render_only false)}}
<div class="input-group {{#if is_disabled}}control-label-disabled{{/if}}">
    <label class="checkbox">
        <input type="checkbox" class="{{setting_name}} inline-block setting-widget prop-element" name="{{setting_name}}" data-setting-widget-type="boolean"
          id="{{prefix}}{{setting_name}}" {{#if is_checked}}checked="checked"{{/if}} {{#if is_disabled}}disabled{{/if}} />
        <span></span>
    </label>
    <label for="{{prefix}}{{setting_name}}" class="inline {{setting_name}}_label" id="{{prefix}}{{setting_name}}_label">
        {{label}}
        {{#if help_link}}
        {{> ../help_link_widget link=help_link }}
        {{/if}}
    </label>
</div>
{{/unless}}