If I deactivate and delete the Classic Editor plugin, will the pages automatically revert to Blocks?
No. The existing posts and pages will be loaded in the block editor but won’t be converted to blocks automatically. Will show there as having a single Classic Block. They can be converted by using the “Convert to blocks” button on the Classic block’s toolbar.
Will any data be lost by doing so?
Generally no, but the HTML markup may change so they may look differently on the front-end.
It is not necessary to convert existing posts to blocks even if you don’t use this plugin. They will continue to work/look properly on the front-end, and can be edited in the Classic Block in the block editor.
If you want to convert them, and are worried it may not work, perhaps best would be to open the existing posts one by one in the block editor, convert them to blocks and check how they look on the front-end (and revert to the previous revision if they don’t look right).
Thank you for your help. I really appreciate it.
