@bender-ui: collapsed
@bender-tags: 4.5.10, bug, trac14451
@bender-ckeditor-plugins: clipboard, contextmenu, toolbar, wysiwygarea, image2, sourcearea

## Scenario

1. Switch to source mode.
1. Add an `id` attribute with a value of `100` to the `<figcaption>` element.
1. Switch back to WYSIWYG mode.

### Expected result:

No errors thrown, buttons work.

### Unexpected:

Various errors thrown, buttons stop working - editor is rendered inoperable.
