Dock restoreState fails silently if a dock object is the only item in a V- or HContainer about pyqtgraph HOT 1 CLOSED

I investigated the issue myself already and could trace the origin via the following call stack:
In DockArea.restoreState .buildFromState is called.
buildFromState builds the container layout recursively.
When it builds the vertical container containing Plot 1 it calls obj.apoptose(propagate=False).
Here the dock widget is inserted in the parent container and removed from its original container: https://github.com/pyqtgraph/pyqtgraph/blob/master/pyqtgraph/dockarea/Container.py#L71
Finally the container change is propagated via the call to containerChanged(self): https://github.com/pyqtgraph/pyqtgraph/blob/master/pyqtgraph/dockarea/Container.py#L54
And here finally is the culprit: apoptose() is called on the original container without any arguments: https://github.com/pyqtgraph/pyqtgraph/blob/master/pyqtgraph/dockarea/Dock.py#L213
This means propagate is True, as can be seen here: https://github.com/pyqtgraph/pyqtgraph/blob/master/pyqtgraph/dockarea/Container.py#L60
So, since there is only one element in the container currently and all parent containers have only one element as well, because we're in the middle of constructing the container tree, the entire tree is compacted into only one container and the dock itself.
Now, the container in the further state restoration are missing and therefore not visible and even garbage collected.

Changing Line 213 in Dock.py to self._container.apoptose(propagate=False) fixes the issue and all docks are correctly restored.
The problem is I don't know if this was merely forgotten there, because it is no usual case, that a container has only 1 element or is it necessary because something else would break, which I'm not aware of.
Anyone has any idea?

from pyqtgraph.