TwentyFifteen bug in blog_item.html.twig

Hi, in blog_item.html.twig there's a small omission in the lower nextSibling / prevSibling navigation.

Please change

<span class="post-title" {% if page.nextSibling.media.images %}style="color: #fff;"{% endif %}>{{ page.header.title }}</span>

to

<span class="post-title" {% if page.nextSibling.media.images %}style="color: #fff;"{% endif %}>{{ page.nextSibling.header.title }}</span>
---

Can you please submit an issue on the grav-theme-twentyfifteen repository? Thanks!

Yes, I did something like that - submitted the changes and issued a "pull request". Hope this is what you are suggesting; not sure, because I am totally unfamiliar with Github.