Summary
- merged
- more HTML rendering as in Isabelle/jEdit; tuned;
- tuned signature;
- clarified menu; avoid non-portable ALT-mouse combination;
- clarified signature;
- HTML preview based on PIDE markup;
- explicit foreground color, for the sake of dark theme in VSCode;
- tuned layout (amending 8040d2563593);
- more official session qualifier;
- clarified;