How can I disable image resizing in CKEditor?
According to How to disable the image resize handles ? this is supposedly solved with CKEDITOR.config.disableObjectResizing = true;. 

But even when I change it directly (for testing purposes) in /core/assets/vendor/ckeditor/ckeditor.js 

CKEDITOR.config.disableObjectResizing=!1 to 

CKEDITOR.config.disableObjectResizing=!0
// OR
CKEDITOR.config.disableObjectResizing=1
// OR
CKEDITOR.config.disableObjectResizing=true


It doesn't make a difference, I can still resize. 



So I guess you will have to solve this via CSS. 

If you want them to still be responsive, you could do: 

.some-div img { max-width: 100% !important; } 


OR

.some-div img { max-width: 400px !important; } 


Obviously, this would mean the size in the editor may not reflect the size on the page, but this will do at least in the meantime if you're not satisfied with this answer/approach.