The explorer is running in 'regtest' mode. This saves disk space, but there is limited data.
The code for this application can be found at

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Enter a block height, e.g. 123, or the start of a bitcoin address, e.g. mzaGu

Height: 573
Hash: 7a25d873a321d187fcee5d00ed788d636d4a99912652651344fb752ddfec1d4b
Previous block: 016f6fe42a7177774e7ee3519e8780f1983b94131d7f29b415a771ec3f9c39cb
Next block: 66d9a050f2383095ea4bfc5d31d5919d6ca5fa9187368c2ee0a4af5bba754f28
Weight: 948
Versionhex: 20000000
Version: 536870912
Time: 1564711424
Stripped size: 228
Size: 264
Nonce: 0
Merkle root: e6c1fda2e67216f0a4774e45c0c7a86ff0ec8c837aebfe2bb6d0bc78036ece70
Median time: 1564711424
Difficulty: 4.656542373906925e-10
Confirmations: 31
Chainwork: 000000000000000000000000000000000000000000000000000000000000047c
Bits: 207fffff