AbstractVisionComponent - How to getTagManager

I try to read tag in an AbstractVisionComponent
Ignition 7.6.4rc2

getAppContext() return null, and i can’t use getAppContext().getTagManager() to have an entry point to the Tagmanager for reading tag.

Is it a bug ?
How to read/write/subscribe Tag into an AbstractVisionComponent ?

Just out of curiosity, why would a component need to look at a specific tag? Wouldn’t you just create a property for that component and let the user define what tag to assign to it?

For my vision component (a video player) I need to know if the designer is in preview mode or not.
To achive it, I doesn’t founded any other method than reading the [System]Client/System/SystemFlags.
I Kwnow i can add a property on my component for binding this tag on it, but it would be user friendly to avoid this property, by reading the value inside the component.

[Edit: wrong thread, moving to correct thread, see viewtopic.php?f=74&t=11223]