pyfedi/app/templates/post/_post_notification_toggle.html

<a href="{{ url_for('post.post_notification', post_id=post.id) }}" rel="nofollow" aria-live="assertive"
   aria-label="{{ 'Notify about replies to this post.' if post.notify_new_replies(current_user.id) else 'Do not notify about new replies to this post.' }}"
class="small fe {{ 'fe-bell' if post.notify_new_replies(current_user.id) else 'fe-no-bell' }} no-underline"
hx-post="{{ url_for('post.post_notification', post_id=post.id) }}" hx-trigger="click throttle:1s" hx-swap="outerHTML"
title="{{ _('Notify about replies') }}" aria-label="{{ _('Notify about replies') }}"></a>