Featured servers from the unreleased Servers tab in the new UI appear as LAN servers in Friends tab on the old UI, but disappears after some time switching back from the new UI.

Steps to produce:

1: on the menu, Click "Play"

2: if you're not in the new UI, click "Switch to New UI" on "Worlds" tab to switch to new UI

3: Wait for at least 5 seconds

4: Switch back to old UI by going to "Servers" tab on the new UI, and then click "Return to old UI" (I cannot see the Featured Servers in Servers tab on the new UI by the time I was creating the bug so I assume it was not released for now on Minecraft Preview, I use Windows PC and iOS to produce the issue.)

Expected result: Featured servers do not appear as LAN servers on "Friends" tab on the old UI after switching back, only in "Featured Servers" in the "Servers" tab on the old UI and only the LAN (Local-Area-Network) servers you're hosting in your network show as "LAN" in "Friends" tab.

Actual result: After returning back to the old UI, You might see that there were some servers running on "Friends" tab, these last for ~5 seconds and they disappear after that, and these are some LAN servers that have the same names and descriptions as some of featured servers on "Servers" tab on the old UI, what I suspect is these (hidden) featured servers from the new UI were being put as LAN servers in the old UI.