When change the scaled ratio of the browser, the ui becomes abnormal

I use emcc to compile my demo to run on the web,

then i change the scaled ratio of the browser to 90% or less , the ui become abnormal,

use layout or not is the same result.

and  whenever i change the scaled ratio the console output "The cached device pixel ratio value was stale on window expose.  Please file a QTBUG which explains how to reproduce."