Edit Flow, the modular editorial plugin that enables collaboration inside the WordPress admin, is no longer being actively developed. After no updates for nine months, Mark Warbinek, a frustrated user, contacted Automattic to ask if they have abandoned the plugin or still plan to update it. A support representative from Automattic confirmed the company will no longer be updating Edit Flow:

At this time there is no active development of the Edit Flow Plugin.

That being the case – two things I can suggest are:

Submitting the issue to the Github repository for the plugin. This is used to track future development of the plugin and will be a canonical place for bugs or issues to be recorded.
https://github.com/Automattic/Edit-Flow

It is possible to ‘fork’ the plugin and make the changes needed – or use an alternative that has already been forked like PublishPress:
https://github.com/Automattic/Edit-Flow

Edit Flow is active on more than 10,000 WordPress sites and its sporadic development has caused users to question whether it was abandoned several times over the years. It is still listed among the WordPress.com VIP plugins, but will likely only be maintained for that platform going forward. A 10-month old PR was merged on its GitHub repository as recently as 19 days ago, after the contributor began to question whether the project was abandoned.

In 2016, Edit Flow went two years in between updates, leaving frustrated users in the dark. After that incident, a representative from Automattic said the company was working on an internal effort to improve the maintenance of their own plugins in order to avoid a situation like this happening again. The company currently has 88 plugins listed in the official directory.

PublishPress is the only alternative editorial plugin with comparable features, including an editorial calendar, notifications, editorial comments, custom statuses, and a content overview. It also offers seamless migration of Edit Flow data to PublishPress. A commercial version of the plugin includes additional features, such as a publishing checklist, reminders, permissions, a WooCommerce checklist, and more.

“I think I can speak for those users of this plugin that we are not happy with the horrible handling of this plugin, how Automattic has ignored and abandoned it, leaving users to suffer in the continuing fails this out-of-date plugin is causing,” Mark Warbinek said in response to to the reply from Automattic’s support team.

Unfortunately, this is always a risk when using free plugins from WordPress.org, especially ones without a direct business model supporting development. In many instances the plugin author’s first priority will be maintaining it for the paying customers. In this case that is WordPress.com VIP clients. Automattic has not posted an announcement on Edit Flow’s support forums, but an official communication would go a long way towards steering users in the right direction when they inevitably come looking for signs of life in the plugin.