Council has an on-going program of maintaining their footpaths to the appropriate level of safety. Due to various factors (particularly growing trees) footpath segments can often be raised, resulting in a dangerous lip. If you notice any dangerous situation on a footpath, report the problem to Council.
The first indication that Council is aware of a problem is often when they mark the dangerous edge with a yellow marker. Subsequently, the dangerous edge is typically ground to even the adjoining edge.