wenzelm [Wed, 17 Nov 2021 15:54:11 +0100] rev 74815
afford more parallelism for sessions (instead of theories in 5eac4b13d1f1): depend on disjoint data areas (notably base.session_theories in 2ad892ac749a);
wenzelm [Wed, 17 Nov 2021 15:23:15 +0100] rev 74813
present only selected session theories (as in Isabelle2021), in contrast to 2bc24136bdeb, eb89b3a37826;
eliminated implicit state: these theories are globally unique;