Dropped frame or barline not showing in continuous view

In continuous view, some dropped elements aren't updated in the scoreview : barline, horizontal frame. But if we switch to page view, the elements dropped before are shown. Then back to continous view, the elements are correctly drawn.

A way to test this bug is also to drop a Hbox in the middle of the score.
Switch back and forth in page view. This makes the Hbox visible in continuous view
Click on the Hbox and try to change the width with the inspector. The layout doesn't change.

This seems to be caused by the fact that the list of systems is created in the function layoutSystems() not triggered in continuous view.

Line 610 in layout.cpp
if (layoutMode() == LayoutLine)
layoutLinear();
else
layoutSystems(); // create list of systems

Forcing layoutSystems to be executed before layoutLinear() corrects the situation, but this hack sometimes causes a crash after a few additions or changes of elements.