Hi Mert!
All the images are loaded to the server 2600 wide, for wide screen resolutions. And when the page opens it loads all the images in original size, its killing the page loading time
Example page: https://whatiszmist.com/work/pbk/

Can images in the single portfolio post be loaded in smaller size, before they are clicked for full screen(magniifc popup) view?

Does option "Serve Resized Images" respond in some way for this feature? If yes – it is turned on and does not work for me. Or maby I do something wrong…

Here was a post close to this problem in 2015, but I still did not find any solution.
https://northeme.desk.com/customer/portal/questions/14592653-thumbnail-regeneration-doesn-t-work-images-are-full-size