CKEditor on [Webkit/Blink] drops cursor when changes in one editor update another

[David]

1. Go to ​http://ckeditor.com/demo#inline on a Webkit-based browser
2. Bind contents of editor1 and editor2 on a key listener

   CKEDITOR.instances.editor1.on("key", function() { CKEDITOR.instances.editor2.setData(CKEDITOR.instances.editor1.getData()) });
   

3. Update editor1 text.

Expected: editor2 updates. editor1 cursor remains at original place. Observed: editor2 updates. editor1 cursor goes back to start of editor.

Screencast attached. Firefox works fine.

[David]

Screencast of issue

[David]

Further debugging found the issue in CKEditor in selection.js - line 452.

Webkit's selection will mess up after the data loading.

CKEDITOR.env.webkit && editor.on( 'setData', clearSelection );

Would it be enough to only clear the selection if the selection is in the current element?

Is there any possible workaround that can be provided as this issue is blocking us.

[mffiedler]

Add CC

[Jakub Ś]

Problem can be reproduced from CKEditor 4.0 beta in Webkit and Blink in inline editors only.

[Piotrek Koszuliński]

I pushed ​t/11500 with a proposal of patch that solves the problem. I'm not sure if check shouldn't be moved to removeAllRanges() though.

[Olek Nowodziński]

Replying to Reinmar:

I pushed ​t/11500 with a proposal of patch that solves the problem. I'm not sure if check shouldn't be moved to removeAllRanges() though.

I tested your idea for a while

removeAllRanges: function() {
	if ( this.getType() == CKEDITOR.SELECTION_NONE )
		return;

	...
}

...and it looks fine. IIRC, in real-world usage CKEDITOR.SELECTION_NONE is only possible when editor never got focus or setData is being executed. If that's true, I'm OK with the solution because I see no pitfalls.

[Piotrek Koszuliński]

Pushed ​branch:t/11500 on dev and tests.

[Piotrek Koszuliński]

Fixed on master with ​git:9d666dc on dev and 23400e2 on tests.

[David]

This still does not work properly.

Add a listener from editor1 to editor2 and from editor2 to editor1 (this is our use case).

1. Type "a" in editor1. Both editors have "a".
2. Type "b" in editor2. Both editors have "ab".
3. Type "c" in editor 1. Both editors have "abc".

Further typing in editor1 will show the same cursor issue. Attached a screencast.

[David]

Bug reproducible after incorporating fix

[Piotrek Koszuliński]

Unfortunately I can confirm this. The TC is simple:

1. Focus one of inline editors.
2. Start typing in the second one.

The reason why this happens is that the first editor, when blurred locks selection and this code:

function clearSelection() {
	var sel = editor.getSelection();
	sel && sel.removeAllRanges();
}

Gets that locked selection, which is not empty. This code should get real selection (getSelection( 1 )) and that fixes the issue.

However, we should ask why the selection stays locked if there's a setData() call which we know will invalidate the locked selection. Surprise, surprise, this thread moves us straight to ​http://dev.ckeditor.com/ticket/5217#comment:32 which we found during 4.3.3's testing phase. So both tickets will have the same fix apparently.

[Piotrek Koszuliński]

Patch for #5217 fixes this issue.

[Piotrek Koszuliński]

Fixed by #5217 on major.