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 Subject: Announcing Isabelle2020
 To: isabelle-users@cl.cam.ac.uk
 
 Isabelle2020 is now available.
 
 This version introduces many changes over Isabelle2019: see the NEWS
 file for further details. Here are some notable points:
 
 * PIDE: much faster startup of Isabelle/jEdit thanks to more scalable
 session directory structure.
 
 * PIDE: updated Isabelle/VSCode to follow recent moves of VSCode.
 
 * Pure: improved treatment of theorem dependencies and proof terms,
 accessible via command 'thm_deps'.
 
 * Pure: proper treatment of oracles within internal proof objects,
 accessible via command 'thm_oracles'.
 
 * HOL: various library improvements.
 
 * HOL: better organization of HOL-Analysis vs. HOL-Complex_Analysis.
 
 * ML: more scalable export artifacts via XML blobs.
 
 * Scala: support for external IDEs based on Gradle (e.g. IntelliJ IDEA).
 
 * Scala: support for Ubuntu server applications (Linux-Apache-MySQL-PHP).
 
 * System: Isabelle/Phabricator as self-hosted project management platform.
 
-* System: more robust support for Windows.
+* System: update to current Poly/ML 5.8.1 with improved robustness,
+especially on Windows.
 
 * System: improved support for macOS, notably 10.15 Catalina.
 
 
 You may get Isabelle2020 from the following mirror sites:
 
   Cambridge (UK)       https://www.cl.cam.ac.uk/research/hvg/Isabelle
   Munich (Germany)     https://isabelle.in.tum.de
   Sydney (Australia)   https://mirror.cse.unsw.edu.au/pub/isabelle
   Potsdam, NY (USA)    https://mirror.clarkson.edu/isabelle