(Latest update Aug 2021)
We are getting reports that our web-based tools like the Observation Preparation Tool and the Proposal Submission Tool are not responding well to the new MacOS (BigSur) 11.4 and higher. This also affects this Science Helpdesk occasionally. We have so far no solution to this other than to use an older MacOS, a Linux or a Windows operating system instead.
Note that for all our tools, the preferred browser is and remains Firefox. Chrome has some issues and does not function optimal but may be an alternative, whereas Safari is notorious in behaving in unsuspected ways and should be avoided when accessing our tools.
We apologize for the inconvenience and are trying to address the issue to improve the user experience.