Once in a while I get an Uncaught TypeError

```
Uncaught TypeError: Cannot read property 'firstElementChild' of undefined Slet
TypeError: Cannot read property 'firstElementChild' of undefined
at i (https://xxx/js/jquery/sdecima/jquery.resize.min-4.js:1:58)
at HTMLDivElement.r (https://xxx/js/jquery/sdecima/jquery.resize.min-4.js:1:425)
```