Ideally, all banks should be provided with extra capital, in a way that is not penalising but sufficient to reassure markets that indeed no bank will be allowed to fail, even if the economy deteriorates further.
In the EU, work on this was kicked off in 2016 with an initiative launched by the finance ministers 2/5  BIS central bankers' speeches  of the United Kingdom and Germany. As this topic has also kept us at the Bundesbank very busy, we had our say a short time later by presenting initial concrete proposals for increasing proportionality in Europe.