For command-line junkies: diff https://httpbin.org/get ) https://httpbin.org/get?show_env=1 )
Actually this is closer still to the output. Requires colordiff: diff -u https://httpbin.org/get ) https://httpbin.org/get?show_env=1 ) | colordiff
icdiff is also nice to have a side-by-side colored diff (https://github.com/jeffkaufman/icdiff). And of course, you could use meld, vimdiff, kompare etc. with the same bash anonymous pipes indirection.