Hello, I have changed recently my blog theme to the very nice colormag.
It appears that featured image has to be 800 x 445 px to fulfill the post or page head. However, it is going to be very annoying if I have to manually resize all my existing featured images.
Does Colormag possess a kind of automatic crop function to do that?
If not, is there a css trick to do that? (automatic resizing of every old featured images).

Many thanks for your help.

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