[Vue warn]: Error in nextTick: "TypeError: Cannot read property 'focus' of undefined"

Get this occasionally when I switch between components and reopen a modal. When I reload the page with the modal there is no warning. I'm using:

this.$root.$emit('show::modal', 'my-modal')

and

this.$root.$emit('hide::modal', 'my-modal')

I use 0.15.5. When I downgrade to bootstrap-vue to 0.15.0 there is no warning at all.

Similar issue: #19