Vuetify: v-textarea .selectionStart and .selectionEnd return undefined

[vahdet]

I get the values of selectionStart and selectionEnd properties as undefined when I try to apply on a v-textarea instance on a keydown (@keydown) event -which features an event.preventDefault() at the very beginning if it is a necessary thing to point out.

The desired behavior
Return the indices of the start and the end of the selected part.

Snippet for Reprod
https://codepen.io/vahdet/pen/WgJyEw

Select some part of the predefined text here and watch for the values above the v-textarea

[jacekkarczmarczyk]

You need to reference the actual textarea element, not the v-textarea component
https://codepen.io/anon/pen/XPqPYK