Metaboxes for This Day In History posts

Hello,

I tried to add metaboxes for This Day In History posts in “Edit Historic Event” screen.
Especially I was interested in adding metaboxes for SEO and for permalinks. I’m using RankMath. Although in this plugin options there is possibility to turn on SEO meta box for Historic Events (custom posts), it is not visible in editing mode (“Edit Historic Event” screen). But for Event types and “Edit Event Type” screen it works!

So I was trying to do it “manually” by turning on UI (‘show_ui’) for “Edit Historic Event” screen. Unfortunately it was impossible – error was caused: “Uncaught Exception: DateTime::__construct(): Failed to parse time string (Automatycznie zapisany szkic) at position 0 (A): The timezone could not be found in the database in /var/www/vhosts/…/…/…/httpdocs/……/wp-content/plugins/this-day-in-history/tdih-list-table.class.php:219”.

Is there any way to have post editor with metaboxes for tdih_event (like for another posts and taxonomies)?

Btw, thanks for this great plugin,

ls