Is it possible to show the full image in a fixed thumbnail size? I tried doing <?php the_post_thumbnail( 'full', array( 'class' => 'thumbnail' )); ?>. It did showed the full image but the size is not fixed.
I hope you are well today and thank you for your question.
I am not sure what you meant by “full image in a fixed thumbnail size” so could you please describe it a bit more in detail so that i can help you to achieve it?