TextRotation angle is never set in Google Sheet API

Question

I'm using Google Sheets API v4 from Java Client. I'm trying to get format from Cell class. Everything goes fine.

TEXT ROTATION

I'm succeed in getting TextRotation element with Vertical property set but, angle property is never set, what ever I put on source Google Sheets document.

Whatever the angle value selected in Google Sheet App, angle property is never set.

I've tried to inspect returned JSON, to know if the issue is in Java Client.
But JSON REST API also never returns this property.

Current Result:
.
Expected Result:

Answer 1

Finally, I've written a JS Library : screen-rotation.js to manage all this stuff.

screenorientation().change(function(){
 // My event management
});

It supports iOS, Android & desktop browsers