I have done a share between three devices, all sharing in all directions. Those devices are my OnePlus 5T, and two Amazon Fire Kids tablets. Each device uses its own account (mine on the 5T, one tablet for each kid - all paid and unlocked and logged in as their own users). That is the only time and the only devices I have done the share with. Now when I open the Join extension on one of my desktop PCs, I see the fire tablets. When I open Join extension on one of my laptops, I do not see the fire tablets. Why are they visible on one PC but not the other?