Just noting this: There’s also the case of two views to consider. I suppose if both views were open, that counts as a multiple tab situation, so the tab bar would have to be shown.

I never use any right click actions from the tab menu, so losing that “quick” access doesn’t matter. I find it just as easy to find these actions under “file” anyway.

For my use of notepad++, I prefer to have it open files in multiple instances, because otherwise I keep accidentally closing all files, instead of just the one I was taking a quick look at.

So generally I have no use for tabs, but sometimes I have reasons to open several files in the same instance, and for this case, I’d like tabs to automatically show.

I’ve seen many requests for this over the years, but it’s generally just ignored or dismissed, which is strange, since it’s an obvious option to include, that wouldn’t affect anyone not wanting to use it.

there are actions that might be easiest to access from the tab bar right-click menu – even if you only have one document open at the time; by hiding the tab bar

This is a very good point.
The only (slight) downside I can see to showing the tab bar when there is only one document is that a small bit of vertical screen real estate is “wasted”.

I’d forget about it, and just be okay with the tab bar showing, even with only one doc.

Regardless, there’s an open issue on it, and a script workaround; see HERE.

I’m not sure that many would agree with you on that request.

I personally hate when tab bars and similar items disappear or reappear depending on some condition that I may not know about. Further, there are actions that might be easiest to access from the tab bar right-click menu – even if you only have one document open at the time; by hiding the tab bar, you get rid of that easy access to those options. But mine isn’t the only opinion out there, or the only one that matters.

In case you didn’t know: this forum is not the feature request location. If you do want to request such a feature, you will have to follow the instructions in that link. When you do, I suggest including more than one sentence in your request – make it obvious what you are asking for, and make sure to suggest that the option be selectable from the Preferences > General > Tab Bar settings. If you do make a request by following those instructions, make sure you paste a link to that request issue in this topic, so other readers can see that you did.