With NS-Angular on iOS RadCalendar looses style information during transition when used in TabContentItem or when app resumes from background to foreground

Tell us about the problem

Like the title already mentions, I am using a RadCalendar in a Tabs / TabsContentItem . The RadCalendar is styled using a style service according to the usage examples in the NS documentation. The style is most of the time working as expected. But whenever the app is sent to background and resumed the RadCalendar seems to have lost the style information. The default style configuration is applied instead. The same happens when the RadCalender is used in a TabsContentItem, whenever the tab with the calendar transitions out of the view it losses its style information. It seems like this is a systematic bug in NS Angular on IOS which I am hitting here. I observe the same problem with different charts from the ui library. I assume that the following bug is related:

https://github.com/ProgressNS/nativescript-ui-feedback/issues/1335

Which platform(s) does your issue occur on?

iOS

Please provide the following version numbers that your issue occurs with:

    "nativescript-ui-autocomplete": "^6.0.1",
    "nativescript-ui-calendar": "^6.1.0",
    "nativescript-ui-chart": "^7.1.1",
    "nativescript-ui-listview": "^8.2.0",
    "nativescript-angular": "^8.21.0",

tns --version 6.7.4

"tns-core-modules": "^6.5.10" and I also tried with version 6.5.12

"tns-android": {
    "version": "6.5.1"
},
"tns-ios": {
    "version": "6.5.1"
}

Please tell us how to recreate the issue in as much detail as possible.

seems like it appears with a radcalendar with custom styling (styling service according to docs) in a tabcontentitem. Send app to background wait 3 seconds and start app again. Alternatively slide between tabs, radcalendar also looses its styling. Between tabs style is lost on ios simulator and real device. In case of foreground/background switch you have to use a real IOS device (no simulator).

ProgressNS / nativescript-ui-feedback