Re: [PATCH] Address issue with tab-bar

[Juri Linkov]

> I've noticed an issue where, if tab-bar-mode is t, but tab-bar-show is
> 1, then if you open a second tab, then close it, it will hide the tab
> bar and not show it again.
>
> e.g. running the following code will result in two tabs being open, but
> the tab bar not visible.
>
> (customize-set-variable 'tab-bar-show 1)
> (tab-bar-mode)
> (tab-bar-new-tab)
> (tab-bar-close-tab)
> (tab-bar-new-tab)
>
> The below patch addresses this issue by not hiding the tab bar if
> tab-bar-mode is t, in the same way that tab-bar-new-tab-to does.

But according to the documentation of 'tab-bar-show':

  "If the value is ‘1’, then hide the tab bar when it has only one tab,
  and show it again once more tabs are created."

tab-bar-close-tab should hide the tab-bar on the selected frame
with only one tab.

So the problem is that tab-bar-new-tab doesn't show the tab-bar again
when there are more than one tab.

It seems this is a consequence of bug#42052 that tried to implement
frame-local tab-bar where tab-bar-mode is always true, but it shows/hides
frame-local tab-bars depending on the frame-parameter 'tab-bar-lines'.