It randomly happens that zooming by scrolling gets stuck and does not work any more. It usually happens when coming back to the layout window from another window (being it an editor or an analysis tool). It never happens while working on the layout window itself.
“Reset zoom” does what it is supposed to do, but still zooming by scrolling is disabled.
A solution I found is to temporarily switch to Classic view and then switch back to Graph view.
Is anyone facing my same problem?