I also posted this issue on github including a screencast: https://github.com/wpmetabox/meta-box/issues/1322
Metabox version 4.18.4
After scaling an image, closing the editor and opening the editor again, a white screen appears. I am using the "image_advanced".
Steps to Reproduce (for bugs)
Start editing a post.
Click the pencil icon to start editing an image.
Click the "edit image" button"
Scale the image
Click the 'scale' button
Close the edit screen
Click the pencil icon to start editing the same image
Click the "edit image"button
A white screen appears.
Browser: chrome and firefox.
Continue editing the same image.
A white screen. When the page is saved after scaling the issue is resolved. The cropped image can now be edited. Also when leaving the editor by clickick 'cancel' instead of the closing 'X', the problem does not occur.