Also found on redlinked talk pages. Example:

• https://en.wikipedia.org/w/index.php?title=Talk:Sega_3D_Fukkoku_Archives_3:_Final_Stage&action=edit&redlink=1

As can be seen by my comment above, the new invitation to begin a discussion notice is found on all talk page redirects, to include those that are uncreated talk pages of redirects. Do we really want to stimulate inexperienced editors to create a talk page of a redirect and begin a new discussion that nobody will read? They should start that discussion on the talk page of the subject page redirect's target, where it will be read by editors who are involved with the target subject. This might complicate things for you, and forgive me for that; however, this notice does need to be removed from all talk page redirects, both those that have been created and those that have not been created.

Thanks for the bug report!

If I understand correctly, you're talking about two different situations:

1. When the talk page itself is a redirect – In which case you're absolutely right, clearly the new interface shouldn't appear, we just overlooked this case. It was already reported a few days ago at T312599#8110947, and the patch fixing this will be deployed next week.
   
   (Fun fact: when you view e.g. https://en.wikipedia.org/w/index.php?title=Template_talk:Jct/sandbox&redirect=no, note how a "New section" tab is also shown, similarly inviting you to begin a discussion, although less obtrusively. Somehow this has been overlooked for around 15 years, so I think our mistake is excusable. This will also be changed.)
   

2. When the talk page of a redirect page does not exist – In which case you're probably right, but I think the decision is not that obvious. It's probably good to centralize the discussion, but you might conceivably have a discussion about the redirect there, too.
   
   I'd like to note that the old interface didn't make any effort to handle this case, either – there's no edit notice or anything. If we remove our thing, these pages will just revert to this view, so you might also want to propose some changes to this on-wiki. You can view the old interface using the 'dtenable=0' parameter: https://en.wikipedia.org/w/index.php?title=Talk:Sega_3D_Fukkoku_Archives_3:_Final_Stage&action=edit&redlink=1&dtenable=0
   

(For reference, this is also being discussed at https://en.wikipedia.org/wiki/Wikipedia:Village_pump_(technical)#Talkpage_redirects.)

In fact, there's also case 3:

3. When the talk page of a redirect page exists, and is not a redirect. According to this query: https://quarry.wmcloud.org/query/66344 (I'm having trouble with Quarry, but I ran it on production replicas) there are currently 879275 such pages on English Wikipedia! This is actually very surprising to me. Some examples: Talk:Nestle, Talk:Sharp_s, Talk:C_with_circumflex, Talk:K50GO, Talk:Mărăjdia_River, Talk:Erase_(song). It seems to me like in most cases someone really wanted to have a separate discussion page for the redirect?

I have no idea what we should do about this.

Case 2: in the past it's been discouraged. Creating a talk page of a redirect has only been widely done when the redirect has been to RfD. If kept, a notice is placed on its talk page whether or not it has already been created. If something else comes up, usually an edit request, editors have been encouraged to place the edit request on the subject page's target's talk page and place the redirect title in the first parameter of the edit request template.

Case 3: if talk pages already exist, then normally the "Talk page of redirect" template goes at the Top, which "soft" redirects and states "Because this page is not frequently watched, present and future discussions and edit requests should take place at: (name of subject page's target's talk page). So good catch! We don't want to encourage discussion on those pages either. Thank you very much, matmarex!

A little background: when I first saw this notice on the talk pages of redirects, my first thought was that such an invitation to start a discussion should not be found there. Searched and searched for a page in the MediaWiki namespace that applied the invitation as a template, but was unable to find such a page. That's when I brought it here. Talk pages of redirects, whether already created or uncreated, are not watched enough by editors to justify this invitation to start a discussion. Thank you for reading. It is hoped that this is easy to fix on all talk pages of redirects, perhaps with some tool similar to enwiki's https://en.wikipedia.org/wiki/Module:Redirect or something like https://en.wikipedia.org/wiki/Template:Redirect_other.

On English Wikipedia, there are already some customizations in https://en.wikipedia.org/wiki/MediaWiki:Discussiontools-emptystate-title and https://en.wikipedia.org/wiki/MediaWiki:Discussiontools-emptystate-desc – can I suggest that you propose customizing the behavior there for the redirect pages too?

I'm not sure if this is the right thing to do still, but if you can convince someone else on Wikipedia to implement this and no one complains, I think that'd be a good sign that we should do this ;)

Looks like this has been relsolved across all three issues shown above. Thank you very much for all your help, with this and other buggy challenges!

Thanks. It's fine by me if you want to close this, but I have to note that we haven't actually done anything about cases 2 and 3, they still behave like they did before.

I checked and that doesn't seem to be the case: here is a case 2, a talk page of a redirect that has not been created, https://en.wikipedia.org/w/index.php?title=Talk:Annales_des_empereurs_du_japon&action=edit&redlink=1 – and here is a case 3, a talk page of a redirect that is not itself a redirect, https://en.wikipedia.org/wiki/Talk:%22L%22_is_for_Love – neither has the new suggestion to begin a discussion. So someone has fixed this perhaps without knowing about this report?

Yes, Tacsipacsi, my prefs are set to the ''default'' setting, which means the box marked "Enable quick topic adding" is unchecked by default. Editors must check that box to see the empty talk page experience. I'm not sure, but I don't think we want to change that, because that seems to be its purpose. The empty talk page experience has been removed from talk pages when users have not changed their default setting.

Tacsipacsi, please forgive me, as I don't remember ever setting that preference, so I thought that my setting was the default. Not so sure now, because I've already had to show one editor how to alter that setting here: https://en.wikipedia.org/wiki/Template_talk:WMF-legal_banned_user#Template-protected_edit_request_on_1_August_2022. The editor thanked me through notifications, so it seems to have helped. "Enable quick topic adding" (unchecked) may not be the default setting, and if it's not the default setting, then it should be.

It is checked by default on enwiki following this RFC: https://en.wikipedia.org/wiki/Wikipedia:Village_pump_(proposals)/Archive_190#Enabling_the_New_Topic_Tool_by_default

Thank you, matmarex! Then we are still challenged by the fact that it does not belong on the talk pages of redirects under any conditions. Editors should not be invited to begin a conversation there, whethe the talk page does not yet exist, or it exists as a redirect itself, or it is not a redirect and has banner or discussion content.

After re-engaging "Enable quick topic adding" in my prefs, I checked https://en.wikipedia.org/wiki/Talk:Nestle, a talk page of a redirect with content, https://en.wikipedia.org/w/index.php?title=Template_talk:Jct/sandbox&redirect=no, a remote talk page redirect with no content, and https://en.wikipedia.org/wiki/Talk:Sega_3D_Fukkoku_Archives_3:_Final_Stage, an uncreated talk page of a redirect. I do not see the new talk page experience on the first two (nor do I see it at a target talk page, https://en.wikipedia.org/wiki/Template_talk:Jct). I do still see the new talk page experience at the third example, the uncreated talk page of a redirect. For editors to see the new talk page experience on the uncreated talk page of a redirect is still in need of change. That is not a place where we want to encourage new discussions.

https://en.wikipedia.org/wiki/Talk:Psyklopedin shows an example of a talk page of a redirect that has banners but no discussion content. And that page has the new talk page experience. Add discussion and the NTE disappears. Then remove the discussion and the NTE reappears. Again we should not be encouraging discussion on these pages.

https://en.wikipedia.org/wiki/Template_talk:Db-spamuser is an example of a soft redirect that survived a TfD discussion. This also has the new talk page experience, and so is a page where we do not want to encourage discussion.

Soft redirects are technically not redirects; the software doesn’t know that this talk page is to be considered a redirect. But the solution is simple: just edit (or let a template editor/admin edit) Template:Soft redirect to automatically add __NONEWSECTIONLINK__ to talk pages (or all pages, it has no effect on subject pages), which will disable both the Add topic tab and DiscussionTools’ empty talk page experience.

Thank you, Tacsipacis, that is one I've known about, but it seems to me that using NONEWSECTIONLINK is a bandaid that would be needed in other kinds of examples, as well. Hopefully there is a better way to handle these exceptions.

Some of the above examples have been bandaided with NONEWSECTIONLINK. There are still some pages that need to be fixed, such as https://en.wikipedia.org/w/index.php?title=Talk:Sega_3D_Fukkoku_Archives_3:_Final_Stage&action=edit&redlink=1. Thanks to all the devs!