This is a wiki post to list the general types of plugin that users feel they would absolutely require in order to use CP. That is, plugins that people see as deal-breakers. We will be adding good, CP-friendly options as they become available.
eCommerce plugin - Classic Commerce (a fork of WooCommerce) is now available as a stable release. See classiccommerce.cc
Forum plugin -
Contact form plugin - Fluent Forms will always support Classicpress (but not sure how much of these listed requirements it will handle: “should support logic that allows show/hide of form fields based on selections in other fields; ability to populate fields with data passed via query strings; credit card fields that integrate with payment gateways, particularly Stripe.”)
Litespeed caching plugin - Litespeed Cache is made by the people who build Litespeed. They have now officially declared support for ClassicPress.
SEO plugin - An SEO plugin designed specifically for CP has been developed and is now available in the directory - Classic SEO. GD SEO Toolbox Pro definitely supports CP. Slim SEO has also made a commitment to support CP.
Image slider plugin - MetaSlider have stated they will investigate any problems with future CP versions.
Professional photo gallery plugin - [eg NextGen, Envira]
Cookie notice / GDPR plugin -
Redirects plugin -
Role/access management plugin - [e.g. Members by Justin Tadlock, Advanced Access Management] - User Role Editor
Backup Plugin - Akeeba Backup have announced they will supporting CP and said “We’re in for the long ride”.
Remote management plugin - InfiniteWP have tested CP and confirmed that everything works (except we can’t use it to update the CP core). They have said they’ll “definitely consider adding full support for ClassicPress in the near future” if there is enough demand. MainWP have confirmed that they will look into CP integration and intend to carry out testing on CP installs.
2-factor authentication plugin - MiniOrange have said they will be testing with all future ClassicPress releases.
Spamblocker plugin - WP Cerber is reported to be working well with CP.
SMTP plugin - There is now a version developed specifically for CP. https://directory.classicpress.net/plugins/azrcrv-smtp. There also a petition to add this to core - https://petitions.classicpress.net/posts/163/smtp-integration-settings-as-core-plugin
Custom Fields - Meta Box is definitely supporting Classicpress (the developer is using it on his own CP site).
Migration plugin - All-in-one WP Migration have committed to supporting CP.
Forms plugin - Fluent Forms have confirmed that their devs will always support Classicpress.
Ad management plugin - AdRotate fully supports ClassicPress.
Rich snippets plugin -
Reviews plugin -
Newsletter subscription plugin - [e.g. Mailchimp]
Events calendar/manager plugin - Simple Calendar (links to Google calendar) is working well with ClassicPress so far.
Regenerate thumbnails plugin -
Email log - WP Mail Logging has changed hands and now requires >WP5. Best option at the moment seems to be Email Log. See also petition to add this as a core plugin: https://petitions.classicpress.net/posts/190/add-email-logging-feature
Updates Manager / Notification Manager / Auto-Update Disabling plugin - The following have been tested and reported as working: Easy Updates Manager - has nag screen for other plugin suggestions (with dismissal option), but otherwise working flawlessly. Also working on Muiltisite. Webcraftic Updates Manager - the base functionality, ie. disabling / enabling auto-updates globally or individually per item, is working as expected; Multisite: suggests using Multisite Plugin Manager to individually enable or disable the plugin per site. See this post for more details.
Cron Job Management - WP Crontrol is still working well with CP.
A solid option that should be good for the long term. Either built for ClassicPress or the plugin developer has made a definite commitment to maintain CP compatibility.
A good option where the developer seems interested in supporting CP.
Nothing definite yet but possible working options can be noted. This can change at any time, so if it stops working please add that too.