This one has my blood boiling. I am in a sprint Kanban view, and moving a ticket from "In Progress" to "Blocked". The popup appears asking for a comment. So I oblige and fill out the comment with much detail explaining why my issue was blocked. In the Comment toolbar, I then press the Link dropdown but I meant to press the "+" (Other) dropdown. So naturally I press Esc. BOOM. Popup gone. Everything I typed, gone. No way to get it back. Time wasted. Frustration escalated.
Atlassian, for the love of all that is holy, you need to have a confirmation dialog here. If the user has modified the state of the popup, at least give them a way of knowing that pressing Esc will cause the popup to close and their work to not be saved. Countless users have lost more than I have thanks to an errant press of the Esc button. This is entirely preventable on your end. Please do something.