Version 14.3 (14E222b) TabView Error

I'm having serious problems with TabView. When you start a TabView on Version 14.3 (14E222b), it starts with a single item in the trailing position, just like if you already had about 5 tab Items. If you put another tabItem there it vanishes and is replaced by "..." thing. Also, when you tap a tab item appears another row of tab items above it.

Code? Screenshots?

Version 14.3 (14E222b) TabView Error
 
 
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