I received lots of messages , and I will not respond all now, sorry.

I just want to say, that if we do not agree on a definition of tabs that are VERY GENERAL , that means , to be able to programm them from the first version to do everything you think that a tab should/could do , then another implementation/definition of tabs is loss of time.

But as time as you can programm in elisp a buffer/a window to behave as you wish, why it would not be possible to create tabs that could be programmable ? 

Stephen : The junk with the events, etc was just a supposition. If you have better idea, tell us how to do it.