<h3 dir="auto">Version</h3>
<p dir="auto">2.5.17</p>
<h3 dir="auto">Reproduction link</h3>
<p dir="auto"><a href="https://jsfiddle.net/Herteby/r2nb09eg/" rel="nofollow">https://jsfiddle.net/Herteby/r2nb09eg/</a></p>
<h3 dir="auto">Steps to reproduce</h3>
<p dir="auto">As the title says, or just look at the fiddle :)</p>
<h3 dir="auto">What is expected?</h3>
<p dir="auto">The slots should be rendered properly.<br>
The combination of v-for and "fragment" should return an Array of VNodes.</p>
<h3 dir="auto">What is actually happening?</h3>
<p dir="auto">The slots render as "undefined"<br>
It returns an Array of Arrays of Vnodes.</p>
<hr>
<p dir="auto">The problem seems to be that the result becomes an Array of Arrays of VNodes. Seems like it ought to be flattened.<br>
For some reason, if you add an extra element as a sibling, it fixes it.</p>
<p dir="auto">there is a code, which clones the array element</p>
<div class="snippet-clipboard-content notranslate position-relative overflow-auto" data-snippet-clipboard-copy-content="var self = this, item, arr = [];
for(var i in self.items){
    arr.push(self.items[i]);
    if( i == idx){
        item = arr.slice(idx, idx+1);
        arr.push( item.name ? item : item[0] );
    }
}
self.items = arr;"><pre class="notranslate"><code class="notranslate">var self = this, item, arr = [];
for(var i in self.items){
    arr.push(self.items[i]);
    if( i == idx){
        item = arr.slice(idx, idx+1);
        arr.push( item.name ? item : item[0] );
    }
}
self.items = arr;
</code></pre></div>
<p dir="auto">the code works correctly, but the template glues source element and copied</p>