It's the emulation mode. You'll need to force it to use "edge"
From support
"Normally, this issue is due to the SharePoint project when it was created the comparability/emulation is on IE10 (regardless the browser you are, like your case IE11), once you open the SharePoint page it will switch the comparability to IE10, which Qlik Sense does not support and prompt you the error that you are seeing. One way to proof this, open you IE> hit F12 (dev tools) > go to emulation, currently the emulation would be "edge" > go to your SharePoint page > notice the emulation switch to IE10."
