There seem to be a large number of people that either dont know about this feature or give up when they encounter the current bug with it, so instead of replying to every single one of them I decided to make this thread. If you are trying to play with friends, you most likely already faced the frustration overflows can be, but theres an option that lets you travel to your party's overflow called "join in" which you can see by right clicking on your friend's portrait while in the same zone. This option is currently slightly bugged, making it work sometimes, but there are ways to make it work all the time:

• If you cant see the "join in" option and you are in the same zone, rezoning(Char selection/map changing) fixes it. You can tell who needs to do this by checking out the party UI. If someone's location in the party UI is in another map, then that person needs to rezone.
• If you can see the "join in" option but it errors, rezoning fixes it.
• If its still not working, then the other person needs to do it.
• The issue with "join in" not working sometimes or erroring seem to be because of issues with certain overflows, so when you rezone you change to another overflow.
• Avoid playing in your character's home world unless all your party can get in there.

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