I am unable to see the featured image section

Is this with any post editor screen? Asking because your context content linked shows no post types registered with CPTUI.

Are you using Block editor or classic? If classic, click the “Screen options” tab in the upper right and make sure that there’s a “featured images” checkbox available and that it’s checked.

If using block editor, click the vertical 3 dots in the upper right, and then scroll down to “Preferences”. In that popup, click on “Panels” on the left and confirm whether or not “Featured Image” is toggled there.

thank you, I don’t use any editor and found the cause.

I was using “themes” slug that caused issue.
now it is resolved. (I think if there is something which can be added to not take some slugs on plugin it will be awesome)

We do have “themes” marked as reserved but that doesn’t mean that someone couldn’t have managed to get it in by some other way, whether it be settings import or perhaps it was simply registered before we disallowed it.

Good to hear that you found the source of the issue regardless, and thanks for the followup information regarding that.

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