Thank you. In my config, I've also implemented "(setq tab-bar-inhibit-inactive-group-tab-hints t)" which suppresses tab hints on group tabs when inactive groups are being displayed as they are generally superfluous in that case. We could make suppressing tab hints on group tabs when inactive groups are being displayed as the only behavior which is also fine by me.

(defun my/tab-bar-tab-group-format-function (tab i &optional current-p)
(let ((tab-bar-tab-hints
(if (and tab-bar-show-inactive-group-tabs
tab-bar-inhibit-inactive-group-tab-hints)
nil
tab-bar-tab-hints)))
(concat
(propertize
my:tab-bar-tab-group-name-prefix
'face (if current-p 'tab-bar-tab-group-current 'tab-bar-tab-group-inactive))
(tab-bar-tab-group-format-default tab i current-p))))

On Mon, Jul 29, 2024 at 2:28 PM Juri Linkov <juri@linkov.net> wrote:

close 71939 31.0.50
thanks

>> I'd like to propose that `tab-bar' allow optionally showing tabs for
>> inactive groups when `tab-bar-format-tabs-groups' is in force rather than
>> the always-on policy of collapsing inactive groups.
>>
>> The proposed custom variable `tab-bar-show-inactive-group-tabs' is backward
>> compatible for existing users and has no visible changes for people who do
>> not set it to t. I will occasionally set the value locally to alter frame
>> by frame behavior. I've also used a key binding to toggle the behavior to
>> nice effect.
>>
>> I've been using these changes (via advice :override) under Emacs 29.3.
>
> Thanks for the suggestion. I'll try to adapt this for Emacs 31.

I adapted this for Emacs 31 and pushed to master.
Thanks for this feature.