Case C-244/18 P: Judgment of the Court (Second Chamber) of 26 March 2020 — Larko Geniki Metalleftiki kai Metallourgiki AE v European Commission (Appeal — State aid — Capital injections and State guarantees — Concept of State aid — Concept of ‘advantage’ — Private operator principle — Private investor test — European Commission’s obligation to undertake a diligent and impartial examination — Judicial review — Burden of proof — Concept of ‘firm in difficulty’ — Guidelines on State aid for rescuing and restructuring — Guarantee Notice — 2011 temporary framework — Amount of aid to be recovered — Duty of the Commission and the General Court of the European Union to state reasons)