Interesting to see how much they are willing to invest on bitcoin though, it said they manage a net portfolio of $306 billion, that's huge, but I speculate that they could be just testing some grounds on bitcoin and could be investing in millions initially.
I did a bit of digging, and unfortunately the amount of money they allocated to bitcoin seems to still be unknown.
One thing's for sure, they seem to have been interested in the cryptocurrency industry as a whole:
https://asia.nikkei.com/Spotlight/Cryptocurrencies/Singapore-s-Temasek-joins-Facebook-backed-Libra-currency