Hello Martin,
Thanks for your question!
I have been using Opera. I’ve just tried the Chrome with Fluid size Spinner demo StackBlitz project. I have set the height to 100%, like so:
<div id="DIV1" style="width: 100%; height: 100%;">
<jqxSplitter [theme]="'material'" #jqxSplitter [height]="'100%'" [width]="'100%'" [panels]="panels">
<div>
Below is the screenshot of the Chrome browser:

Chrome sill renders the empty page. What browser and what StackBlitz project are you using?