[Bug] Slider causes errors on resize when used inside keep-alive

[AndrewBogdanovTSS]

I was able to get this error when using Nuxt page level keep-alive prop, but I get it's also reproducible with a regular vue router.

How to reproduce:

1. Create an instance of vue-tiny-slider with keep-alive enabled
2. Change route by navigating to another page
3. Try to resize the page

AR:
https://take.ms/KhftN

Uncaught TypeError: Cannot read property 'appendChild' of null

ER
Accessing any document level methods should be safe. If document is not available appenChild should not be executed

[rizalrenaldi]

Does anyone have a solution to this issue?