Featured image meta box does not respect admin_post_thumbnail_size filter

[arpadHegedus]

Describe the bug
admin_post_thumbnail_size filter is not respected when loading the Featured Image meta box image. Instead the full size of the image is shown

[danielbachhuber]

Hi @arpadHegedus,

What image size are you using / expecting in the Featured Image UI?

[arpadHegedus]

In regular WordPress it can be changed using the filter admin_post_thumbnail_size

For a UX best practice I want to show the same size version of the image in the admin as on the frontend. And for listing pages, I sometimes use specific other or custom image sizes. That's what I want to be able to reflect in the admin as well.

[danielbachhuber]

@arpadHegedus I've submitted a pull request to include a new JavaScript filter for this: #8196

I've also created a page for it in my Gutenberg migration guide https://github.com/danielbachhuber/gutenberg-migration-guide/blob/master/filter-admin-post-thumbnail-size.md