It is not possible to prevent text from dropping.

[Jakub Ś]

Steps to reproduce

1. Use below code in CKEditor

   CKEDITOR.replace( 'editor1', {
                   on: {
                       instanceReady: function( evt ) {
                           evt.editor.document.on( 'drop',  function(ev){
                               console.log('precented');
                               ev.data.$.preventDefault();
                            });
                       }
                   }
               } );
   

2. Select and D&D some text.

Expected result

Text should not be dropped.

Actual result

Text is dropped.

Other details (browser, OS, CKEditor version, installed plugins)

Happens in all browsers starting from CKEditor 4.5.0

[Tomasz Jakut]

There wasn't any check if the event hadn't been prevented in the drop handler. Pushed fix to ​branch:t/13879.

[Marek Lewandowski]

Well done! Merged to master with ​git:0f7494b.