if you have more than 10 tabs open pointing to BO jobs for some reason they start to detect a disconnection, this makes that you cannot do anything on those pages because the disconnection disables UI access. If you open a new browser or an incognito window, then you open one of the same jobs that are disconnected on the previous browser you can work properly with this job. If close tabs until you have 5 tabs or less everything starts working again. I dunno what it is related but there is some resource shared between tab that seems block if you have many tabs accessing to it, Could it be the local storage used as cache?