Last opened article takes focus when reopening app in landscape

[43qcc2cn]

I am experiencing a difference when using the app in portrait and landscape.

Portrait (expected):

1. Open the app. A list of unread articles are presented.
2. From a list of unread articles, open an article.
3. In the top left corner there is a "cross" (close) icon. Click on this to return to the list of unread articles.
4. Close the app.
5. Open the app. A list of unread articles are presented.

Landscape (not expected):

1. Open the app. A list of unread articles are presented.
2. From a list of unread articles, open an article.
3. In the top left corner there is a "two arrows pointing at each other diagonally" (minimise ?) icon. Click on this to return to the list of unread articles.
4. Close the app.
5. Open the app. The previously opened article is presented.

Should the experience not be the same for both portrait and landscape?

I'm not sure if this is a bug or user error on my part. If it's the latter, how do I close an article instead of minimising in landscape?

Thanks in advance.