# find any image larger, then 1600x1200
# open any CKEditor (e.g. during content block editing)
# press `Image` button on CKEditor toolbar
# press `Browse Server` button to open CKFinder
# press the `Upload` button (in the CKFinder window) to open OS file selection popup
# select large image, that was prepared earlier and let it upload
# double click on image thumnail in CKFinder to select it
# press `OK` button in CKEditor image selection dialog to add image to the CKEditor
# confirm, that:
* image was uploaded under `/system/user_files/Images` folder
* this is the same image that was selected during test (same CRC, dimensions, etc.)