Subject: Announcing Isabelle2021To: isabelle-users@cl.cam.ac.ukIsabelle2021 is now available.This version introduces many changes over Isabelle2020: see the NEWSfile for further details. Here are various details:* Improved HTML presentation in Isabelle/Scala, using PIDE markup.* Improved PDF document preparation in Isabelle/Scala, using LuaLaTeX.* Isabelle/jEdit: improved monitoring of Java and ML process.* Isabelle/jEdit: improved look-and-feel and IDE feedback.* Pure: improved handling of named contexts and local syntax bundles.* HOL: substantially reworked support for Word library.* HOL: various syntax and library improvements.* HOL: various Sledgehammer and SMT improvements, with updated external tools.* HOL: support for Nitpick/Kodkod in Isabelle/Scala.* ML: routine support for Isabelle/Scala functions in Isabelle/ML.* System: support for Isabelle/Scala services defined in user-space.* Support for macOS Big Sur on Intel and Apple Silicon (ARM).You may get Isabelle2021 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