We now have a sample email/message that people can use to send to the developers of their favourite plugins.
It has been added to the online FAQs, but I will paste it here too, that seems easier.
You might already have heard of ClassicPress (https://www.classicpress.net), the hard fork of WordPress 4.9.8. It’s in Beta 1 now and the team is working hard on the first production release, ClassicPress 1.0.0. Version 1.x of ClassicPress will always stay backward compatible with WP 4.9.x.
Although I have read that you are working hard to make [PLUGIN_NAME] compatible with the new editor that WP will introduce in version 5.0, I assume (hope) that it also remains compatible with earlier versions of WordPress, such as 4.9.8?
I really hope it is, because as long as your plugin remains compatible with WP 4.9.x, it will also be compatible with version 1.x of ClassicPress.
You probably know this already, but there is even a handy condition that you can use in your plugin:
function_exists( 'classicpress_version' )
And if you want to go even further, you can add somewhere in the plugin’s
readme.txt that your plugin is compatible with ClassicPress. Once you do, it will be very easy for people to search in the WP Plugins Directory on ClassicPress compatible plugins: https://wordpress.org/plugins/search/classicpress/
Looking forward to hearing from you,
Thank you very much,