Whenever you re log the Scoreboard changes from what you had it set (lets say 6 items) to all the possible names, which also include things at 0. Also when this happens it wont show items that have a numerical value above 0 on the top of the list. So it'll be hidden. I am not sure if this is a bug. But it causes problems to see certain items on the scoreboard.
Picture 1: What it supposed to show
Picture 2: What it shows when you re log.
Is this still a concern in the current Minecraft version? If so, please update the affected versions in order to best aid Mojang ensuring bugs are still valid in the latest releases/pre-releases. If this has been done, we can reopen the issue.
Keep in mind that the "Resolved"-Status on this ticket just means "Answered", and that we are waiting for further information on whether this issue still exists or not. We will reopen it as soon as the requested information has been delivered.