I have not tried to replicate this bug, but I do believe that it happened because the last echo I was in I completed the objective but got killed. Instead of pressing the respawn button I clicked open portal and was able to click it when dead. After that this occurred.
There were no enemies on any of the echoes on the lvl 80 timeline only fog and boss objectives. I did not check if other timelines were affected. I could also not pick up any gold and any echo with the spire objective did not spawn the spires.
