Due to Adobe will end support of Flash Player on December 31, 2020, whereupon mBlock 3 web editor that runs with Flash Player will no longer be available for browsers including Chrome, Apple Safari, Microsoft Edge, IE, Mozilla, etc.
Besides, mBlock 3 Mac version will no longer work on macOS Catalina 10.15 and above since 32-bit app support is no longer available on any future macOS versions. Please back up your data in case of data loss.
Please note that you can still run mBlock 3 desktop versions on Windows 7+ and macOS under Catalina 10.15.
After over one year of hard work, mBlock 5 now not only supplies all the needs that are met in mBlock 3, but also updates with many new features. So we would like to recommend you mBlock 5 for teaching or learning coding.
Thank you for working together with us on making mBlock better, and see you in mBlock 5!
If there's any feedback, please feel free to let us know through the Makeblock forum or see FAQs or email our support team with subject line: [mBlock 3 web editor issue] to firstname.lastname@example.org.
The mBlock Team
November 18, 2019