To reproduce:
0. Make sure your cursor is nowhere near the tab suggestion box
1. Type in /team option someTeam
(with a trailing space)
2. Hit tab twice - color
will now be the chosen value (in the chat bar)
3. Hit the down arrow thrice - nametagVisibility
will be the highlighed value (colored yellow in the tab suggestions box)
4. Hit tab - seeFriendlyInvisibles
will be placed in the chat bar instead of the value I just manually highlighted from the suggestion box (seeFriendlyInvisibles
is the value after the one I had highlighted)
Note that step 3 can also be done with your cursor. Expected behavior would be for step 4 to fill the highlighted (yellow) value into the chat bar.
18w06a partially fixed this issue, but selecting a different value by moving your cursor still is affected.
Affects 1.13-pre6. Please keep the ticket updated.