Hi Chen,
Thanks for reporting this problem! We reproduced it on our end and will do further research to figure it out. We will keep you posted about the progress.
It works well on IWA application. If an application runs as IWA (Installable Web Application), it adopts the user interface theme of the underlying operating system, please test if IWA application can meet your requirement.
IWA applications run outside of the Web browser and eliminate the need to configure/install browser plugins. If you are interested, please try the feature here on the following link:
https://support.appeon.com/index.php?/News/NewsItem/View/87
Regards,
ZhaoKai