Hi ​@atomar, thanks for posting, and my sincere apologies for the trouble. Yesterday (1/20), Lucid experienced a brief outage that I believe was the cause of this error. 

Our development team has resolved the issue yesterday afternoon (~3pm MST.) We understand how disruptive this must have been, and we sincerely appreciate your patience and understanding while we worked to address it.

If you notice any further issues, please don’t hesitate to let us know right away, and we’ll be here to assist.

Thank you for your message. We love Lucid and do a lot of work on it, using many integrated sheets with Jira and databases, among other services. This particular sheet we have, however, is not connected to any service; it is a standalone Lucid document shared with many people internationally. I appreciate your reply, and while the specific error is resolved, the sheet remains painfully slow. I often have to select an object, go answer a few emails, and then come back to edit it. Performance is still a problem, and the browser frequently displays a "page unresponsive" error. I usually select "wait" and go answer a few more emails. Because this Lucid sheet is very important, I still believe there has to be a way to improve its performance. Currently, the workaround is to create many smaller, independent Lucid sheets, but that disrupts workflow and introduces delays.

Hi ​@atomar, thank you for providing this information and I am truly sorry for the continued trouble here!

I have created a ticket with our Support team who will assist you shortly in order to have a closer look.

We appreciate your help and patience!