Hi there
Thanks for posting this, Louis.
I am experiencing the same this morning - I had a look at the https://status.atlassian.com/ page and all are Operational. But on few refreshes and some collegues doing the same doesn't resolve this.
It is displaying the error in the summary above either in the center of a blank page:

or on the bottom left:

Please advise where the issue is and how to better monitor this for our org?
Thank you
Yatish