Clearer theme suggestion lists

Could you please post a screenshot, so people could do a visual review.

I totally agree that this looks much better, even if it will maybe need a lot of space.

Yes! Looks great!

But I'm the only one who is seeing duplicates? o_O

I mean that in the same group there a duplicates

views-view--default.tpl.php is listed twice just after each other

This is the cod used to generate such a theme suggestion:

    $themes[] = $hook . '__' . preg_replace('/[^a-z0-9]/', '_', strtolower($view->tag));

    // Add theme suggestions foreach single tag.
    foreach (drupal_explode_tags($view->tag) as $tag) {
      $themes[] = $hook . '__' . preg_replace('/[^a-z0-9]/', '_', strtolower($tag));
    }

So basically you get one theme suggestion for all tags, and one theme suggestion per tag.
I kind of agree that it would be possible in d8 to drop the first line as it is hard to see a use-case to use multiple tags as one key for the theme suggestion. Do you have any oppinion regarding that?

Moved out this discussion in #1782980: Only provide theme suggestions for each views tag, not one for all

Let's get it in and fix the rest in the other issue. Committed and pushed to 8.x-3.x

Back-port for 7.x-3.x-dev

Re-attach patch for testing.

The 4 year old back-ported patch in #14 to views_plugin_display.inc applied cleanly to the latest views 7.x-3.x-dev and works great for me.

Committed. Thank you.