I would suggest posting this into ArcGIS Ideas for StoryMaps so that the community can "kudo" the idea as popular ideas tend to be considered by the development team.
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@BrianMoT -- That isn't something that's currently supported, so it's not a best practice to not add a story title.
If you are expecting your audience to read this story on a phone I would recommend a different treatment. If you look at the story on a small screen you'll see that your title image is not visible in the way you expect (the title text is truncated on both sides). Even if the image fit to the screen, the words in your image would be very small because phone screens have such a different aspect ratio than desktops/laptops.
I can see the look you are going for, but unfortunately that isn't compatible with the current configuration options. As @Kanin mentioned, it would be good to add this to the ideas board with some information about the configuration options you'd like to see so others can weigh in and vote on your suggestions.
Thank you for your replay OwenGeo!
I will post this into ArcGIS Ideas for StoryMaps.
I saw this issue with the mobile, but in this case, I am creating the story for the third part and they want their image instead of the title. They do not like the untitled tab as well. So I am stuck a little bit. I was thinking about changing the colour of the title to the same as the background, but there are no possibilities to edit the colour of the title either... :)
I've also occasionally used a storymap without a title (e.g. if embedding it into another site and not wanting the title to appear). It would be great to have a way to give the storymap a title so that it can easily be found again when editing is needed!
I've upvoted the suggestion in the ideas forum.
PS love the colours in your storymap @BrianMoT !