Here are some succinct instructions the same person sent me which might be of use for such a page. Obviously presented without having tested myself!
(a) security thing. (source: https://ask.sagemath.org/question/49572/sage-90-installation-issues-on-macos-10152-catalina/) sudo spctl --master-disable (b) Jupyter thing. (source: https://groups.google.com/forum/#!topic/sage-support/lpttXB8cjBY/discussion) 1) Grant Full Disk Access in System Preferences->Security->Privacy (as suggested previously) 2) Launch Sage from the command line in the executable's installed directory. In a terminal window: cd /Applications/SageMath-9.0.app ./sage -n 3) The executable should "patch" or rewrite all of the required paths to match their actual locations in your particular Catalina install. After that, it should open a Jupyter tab in Safari. 4) When you see the Jupyter tab in Safari: click the Quit button. This will stop the Jupyter Server, but that's ok. 5) Launch Sage using Applications->SageMath-9.0. -- You received this message because you are subscribed to the Google Groups "sage-devel" group. To unsubscribe from this group and stop receiving emails from it, send an email to sage-devel+unsubscr...@googlegroups.com. To view this discussion on the web visit https://groups.google.com/d/msgid/sage-devel/66cc7e9b-1b83-42ce-968a-ef130ee4d579%40googlegroups.com.
