App killed when starting a foreground activity on some devices

Environment
Provide version numbers for the following components (information can be retrieved by running tns info in your project folder or by inspecting the package.json of the project):

• CLI: 6.5.0
• Cross-platform modules: 6.5.1
• Android Runtime: 6.4.1
• Plugin(s):
  @nstudio/nativescript-checkbox
  nativescript-bitmap-factory": "^1.8.1",
  nativescript-bluetooth
  nativescript-camera
  nativescript-drawingpad
  nativescript-feedback
  nativescript-fonticon
  nativescript-geolocation
  nativescript-iqkeyboardmanager
  nativescript-localize
  nativescript-modal-datetimepicker
  nativescript-print-zebra
  nativescript-printer
  nativescript-sqlite
  nativescript-sqlite-commercial
  nativescript-sqlite-encrypted
  nativescript-toasty
  nativescript-zip

Describe the bug
On some devices, at least on Huawei Mediapad T5, when I start a new activity that goes on the foreground, the NativeScript activity gets killed. When I go back, the NS activity restarts.
After some investigation, I concluded that it's a battery management issue. Android always kills app activities put in the background to minimize battery usage, but on some devices (mainly Huawei from what I've found) this mechanism is very aggressive and kills the activity immediately after it goes in the background. The Android activityDestroyed event and NS exit event are not called.

I have two scenarios:

• Opening the camera with nativescript-camera plugin. The NS activity is killed but the camera still works, allowing me to retrieve the photo uri on restart.
• Printing with the system service PrintManager. In this case, when the NS activity is killed the print tool closes too. To the user, it looks like a crash.

My goal is to prevent the perceived crash at least on the second scenario. Is there a way to release enough resources when the activity is paused?

Allowing the app to ignore battery optimization and managing manually launch/app launch doesn't solve the issue.

To Reproduce
Launch the nativescript-camera demo on an affected device.

Expected behavior
The NS activity is not killed after it starts a new activity.

从 NativeScript 相机演示开始，在受影响的 Huawei Mediapad T5 上复现生命周期。启动相机或 Android PrintManager 时，跟踪 activityDestroyed 和 NativeScript 退出事件，然后将结果与预期行为进行比较：启动前台 activity 后，NativeScript activity 仍保持可用。