I recently installed Drupal 8 to familiarize myself with this platform. I've noticed that, whenever I create an Article, and attempt to upload an image for that article, the styles created from that upload don't work and result in broken links.
In the Article view under Add Content, I have uploaded a small 312 KB file.
The thumbnail preview (red) does not work here, nor elsewhere, and attempting to visit the link generated for this thumbnail results in a 403 Forbidden result: mysiteurl.com/sites/default/files/styles/thumbnail/public/2015-12/Untitled.gif?itok=Y40Z0DEa
The link to the image uploaded (blue) works just fine. Clicking that link displays the image: mysiteurl.com/sites/default/files/2015-12/Untitled.gif
Last detail: I see that this error extends to the Styles configuration screens as well, where the default image on the left side displays fine whereas the right-hand, style-applied preview is broken (and attempting to display the image in a new browser tab, just like the preview in the Article screen, results in a 403 Forbidden result).
How would I go about resolving this? I don't think it's GD, following the directions outlined in a troubleshooting page on Drupal (I cannot post more than two links, due to reputation) I see in the Configuration area for my site that I have a writable file system, and GD installed - bundled (2.1.0 compatible).
I may be coming from left field here, but might the 'Styles' directory be the culprit? If there's some way I can have this folder get regenerated by Drupal, I wonder if that would resolve these errors.