Hmm, wait, this is strange…
The things above happen while using Firefox 39 (up-to-date) on a MacBook Pro. Visiting the URL https://marcbijl.nl/sitemap_index.xml in Chrome 44 (up-to-date) everything seems fine: I get a white window, no errors, and when viewing the source I get this – which seems pretty allright to me:
<?xml version="1.0" encoding="UTF-8"?><?xml-stylesheet type="text/xsl" href="//marcbijl.nl/main-sitemap.xsl"?>
<sitemapindex xmlns="https://www.sitemaps.org/schemas/sitemap/0.9">
<sitemap>
<loc>https://marcbijl.nl/post-sitemap.xml</loc>
<lastmod>2015-08-05T21:27:47+02:00</lastmod>
</sitemap>
<sitemap>
<loc>https://marcbijl.nl/page-sitemap.xml</loc>
<lastmod>2015-01-20T21:10:26+01:00</lastmod>
</sitemap>
<sitemap>
<loc>https://marcbijl.nl/attachment-sitemap.xml</loc>
<lastmod>2015-08-05T21:19:20+02:00</lastmod>
</sitemap>
<sitemap>
<loc>https://marcbijl.nl/portfolio-sitemap.xml</loc>
<lastmod>2014-10-07T22:13:15+02:00</lastmod>
</sitemap>
<sitemap>
<loc>https://marcbijl.nl/category-sitemap.xml</loc>
<lastmod>2015-08-05T21:27:47+02:00</lastmod>
</sitemap>
<sitemap>
<loc>https://marcbijl.nl/portfolio_entries-sitemap.xml</loc>
<lastmod>2014-10-07T22:13:15+02:00</lastmod>
</sitemap>
</sitemapindex>
<!-- XML Sitemap generated by Yoast SEO -->
I’ll do some extra research on this, and come back to you guys…