<p dir="auto">In 3.0.0-rc1 having an element with the <code class="notranslate">hidden-sm hidden-md</code> classes will only hide it for medium devices and not for small ones as well.</p>
<p dir="auto">Navbar.less file has the following definition of the .navbar-fixed-... styles:</p>
<div class="highlight highlight-source-css notranslate position-relative overflow-auto" dir="auto" data-snippet-clipboard-copy-content=".navbar-fixed-top {
  top: 0;
  border-width: 0 0 1px;
}
.navbar-fixed-bottom {
  bottom: 0;
  margin-bottom: 0; // override .navbar defaults
  border-width: 1px 0 0;
}"><pre class="notranslate">.<span class="pl-c1">navbar-fixed-top</span> {
  <span class="pl-c1">top</span><span class="pl-kos">:</span> <span class="pl-c1">0</span>;
  <span class="pl-c1">border-width</span><span class="pl-kos">:</span> <span class="pl-c1">0</span> <span class="pl-c1">0</span> <span class="pl-c1">1<span class="pl-smi">px</span></span>;
}
.<span class="pl-c1">navbar-fixed-bottom</span> {
  <span class="pl-c1">bottom</span><span class="pl-kos">:</span> <span class="pl-c1">0</span>;
  <span class="pl-c1">margin-bottom</span><span class="pl-kos">:</span> <span class="pl-c1">0</span>; <span class="pl-c1">/</span><span class="pl-c1">/</span> override .<span class="pl-c1">navbar</span> <span class="pl-ent">defaults</span>
  <span class="pl-ent">border-width</span><span class="pl-kos">:</span> 1px 0 0;
}</pre></div>
<p dir="auto">It would be better if the border width (1px) was defined via a variable. With the fixed 1px value. to override it, I need to create a duplicate entry for the styles in a CSS file. It would be easier to use a variable, which could be overwritten by a custom LESS file (the preferred approach for style customization).</p>