I can confirm the issue, thank you for reporting. We will fix it in the next 5.2 update.
As the issue occurs only in the GPL edition of the library (the one available on cdn) you can get a free trial version of the PRO edition as a temporary solution.
It works fine with the latest Pro (Commercial) version, 5.1.4 will do the job as well. The bug is in the free GPL version and it will be fixed in the next release (5.2).
Your snippet works for me. But I have exactly that code, and even when using the downloaded trial version, it doesn’t work for me. Same error. I may need to wait for 5.2 … any idea when that might be? I still have lots to do with this, so no hurry.
I think the issue is with views that are inside a multi-view. When I create a page with just the report and a print button, like your snippet, printing works with the downloaded webix (not the CDN version). But when the report is in a multiview, that is when I get the “window.print is not a function” error. So the multiview seems to be causing a problem as well.
But this only happens when I try to print a datatable that is in a multi-view. If I remove the multi-view and have the datatable alone, then printing works. So I think it’s something to do with the multi-view.