How to best protect laptop charger cord against fatigue breakage?

It has happened multiple times to me already that after a number of months of usage the cord of a Lenovo laptop charger starts to show breakage directly behind the laptop connector. A breakage that progressively gets worse until at some point the charger is unable to charge the laptop anymore.

Though the laptop and the charger were always used intensively and in mobile setups, I haven't done anything with the charger that I would classify as abnormal use. I did not constrict the charger cord or bend it myself near the connector with real force.

Last time I put a "sleeve" of sugru mouldable glue around the cord directly behind the connector, but unfortunately also this did not prevent a breakage directly behind the connector occurring over time once again.

A repairman that I talked to advises against trying to fix the cord breakage because he cannot guarantee that any fix will be safe.

If I buy again a new charger, what other modifications could I make myself to better protect the charger cord against this kind of fatigue breakage?