Marine requirements for floating drydocks are non-existant. They fall under insurance requirements as far as I know because they are attached to land. Anyone can correct me if I am wrong.
Halifax Shipyard lost one of their docks about 10 years ago to a sudden failure.
A Chief Engineer told me about having to call the docking manager in the middle of the night because of a sudden list of another dock.

So this happened in Russia:

https://gcaptain.com/worlds-biggest-dry ... t-carrier/

I was on a dry-dock in Vancouver, and the dock master told me some hair-raising things about the state of it.
Been running since seventies yet no dry-docking of the dry dock despite it being made to do so.
Patches on patches, plenty of scantling just replaced in small sections - more wastage somewhere else?

Apparently there was a loud snap from the Halifax dock and she went under with all the equipment stored on it. Good thing Davies reopened, those floating docks were the only ones on the east coast that could lift the Louis S St Laurent. She’s too wide or can’t get over the sill of the rest.