With the arrival of the new Blocks field in 3.5, we are phasing out support for the Editor plugin. You can read more about it here: https://forum.getkirby.com/t/the-end-of-the-editor-plugin/21167 If you need help with the migration, please let us know: firstname.lastname@example.org
Kirby and the Kirby Editor plugin are not free software. In order to run Kirby and the Editor plugin on a public server you must purchase a valid license. The Editor is free for all Kirby license owners.