Evans, great thanks for info how to fix, it works fine. I have written bash file for the users that are not so technical.
Instructions: 1. Download file patch.sh from my post. 2. Open terminal, default keyboard shortcut is: CTRL+ALT+T 3. Set execution permissions: chown 700 patch.sh 4. Execute commands: ./patch.sh 5. Then you can delete patch.sh file: rm patch.sh Hope this helps for others too. P.S. For non-technical users, package maintainer that has packaged original Calibre program in Ubuntu 20.04, please update the package and push it to official Ubuntu repository. ** Attachment added: "patch.sh" https://bugs.launchpad.net/ubuntu/+source/calibre/+bug/1898904/+attachment/5421362/+files/patch.sh -- You received this bug notification because you are a member of Ubuntu Bugs, which is subscribed to Ubuntu. https://bugs.launchpad.net/bugs/1898904 Title: Calibre crashes at startup with AttributeError: 'NoneType' object has no attribute 'cancel' To manage notifications about this bug go to: https://bugs.launchpad.net/ubuntu/+source/calibre/+bug/1898904/+subscriptions -- ubuntu-bugs mailing list ubuntu-bugs@lists.ubuntu.com https://lists.ubuntu.com/mailman/listinfo/ubuntu-bugs
