Errors in the Chrome's console

I see errors in the Chrome console.


I'm still not sure exactly when this happens. I did the same things in both the quote field and the caption field and got errors.

What I did:
1) Enter a line and press 'Enter'(one or more).
2) In the empty line press 'Backspace'
3) I see the error in the console

But sometimes after the same steps, the error doesn't show. You can see it again if you press 'Enter' more than 2 times, enter a line, place the cursor on a blank line below the first line and press Backspace'

this is my config for quote: `{ class: Quote, inlineToolbar: true, shortcut: 'CMD+SHIFT+O', config: {
captionPlaceholder: this.$t('Author name') // this.$t() - it's i18n translation function
}}`