Hitting the "ignore" button on a user make all other users have the "unignore" button instead of "ignore".
You expect to see a "ignore" button on the second user but you see the "unignore" button instead.
Edit: The issue doesn't appears if the user panel is closed then reopened.
The bug can be seen on the right part of this video:

Having the same, using riot with rambox.
I discovered a workaround though:
The user tab doesn't seem to refetch the data about the users, when you click on another user.
This no longer happens

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This no longer happens