Let Standalone users filter friends who aren't in Standalone compatible worlds
Elliot-VR
A filter option on the top of the screen, letting you choose to only view people on blue or green that you can actually join
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Docteh
I haven't checked recently, but one time when I was on quest, it said some friends were in a private world, rather than admit that they were in a PC only world.
I mention this, because I feel that an option to filter down to joinable friends would be a very good feature regardless of details. If someone is on green in an invite only instance, can't join that.