Backtracking problem on the last update of Krita

[Takiro]

With arrows, do you mean the undo/redo buttons?

Undo symbol

Those have been moved to the Edit-Toolbar. Click on Settings → Toolbars shown and there check the one with no name (don’t know if that’s fixed by now). You can also configure the Toolbars to your liking by opening Settings → Configure toolbars… and then you can put the Undo/Redo button somewhere else too if you want.