I have some code in the v4 JSAPI that is attempting something similar to the following example:
Access features with click events | ArcGIS API for JavaScript 4.2
However, IE11 is not resolving response.results() - you can see this manifest in the demo. Check out line ~81, which is the function getGraphics() - you can see the results are empty:

<SPAN class="keyword token">function</SPAN> <SPAN class="token function">getGraphics</SPAN><SPAN class="punctuation token">(</SPAN>response<SPAN class="punctuation token">)</SPAN> <SPAN class="punctuation token">{</SPAN>
<SPAN class="comment token">// the topmost graphic from the click location</SPAN>
<SPAN class="comment token">// and display select attribute values from the</SPAN>
<SPAN class="comment token">// graphic to the user</SPAN>
<SPAN class="keyword token">var</SPAN> graphic <SPAN class="operator token">=</SPAN> response<SPAN class="punctuation token">.</SPAN>results<SPAN class="punctuation token">[</SPAN><SPAN class="number token">0</SPAN><SPAN class="punctuation token">]</SPAN><SPAN class="punctuation token">.</SPAN>graphic<SPAN class="punctuation token">;</SPAN>
<SPAN class="keyword token">var</SPAN> attributes <SPAN class="operator token">=</SPAN> graphic<SPAN class="punctuation token">.</SPAN>attributes<SPAN class="punctuation token">;</SPAN>
<SPAN class="keyword token">var</SPAN> category <SPAN class="operator token">=</SPAN> attributes<SPAN class="punctuation token">.</SPAN>CAT<SPAN class="punctuation token">;</SPAN>
<SPAN class="keyword token">var</SPAN> wind <SPAN class="operator token">=</SPAN> attributes<SPAN class="punctuation token">.</SPAN>WIND_KTS<SPAN class="punctuation token">;</SPAN>
<SPAN class="keyword token">var</SPAN> name <SPAN class="operator token">=</SPAN> attributes<SPAN class="punctuation token">.</SPAN>NAME<SPAN class="punctuation token">;</SPAN>
dom<SPAN class="punctuation token">.</SPAN><SPAN class="token function">byId</SPAN><SPAN class="punctuation token">(</SPAN><SPAN class="string token">"info"</SPAN><SPAN class="punctuation token">)</SPAN><SPAN class="punctuation token">.</SPAN>style<SPAN class="punctuation token">.</SPAN>visibility <SPAN class="operator token">=</SPAN> <SPAN class="string token">"visible"</SPAN><SPAN class="punctuation token">;</SPAN>
dom<SPAN class="punctuation token">.</SPAN><SPAN class="token function">byId</SPAN><SPAN class="punctuation token">(</SPAN><SPAN class="string token">"name"</SPAN><SPAN class="punctuation token">)</SPAN><SPAN class="punctuation token">.</SPAN>innerHTML <SPAN class="operator token">=</SPAN> name<SPAN class="punctuation token">;</SPAN>
dom<SPAN class="punctuation token">.</SPAN><SPAN class="token function">byId</SPAN><SPAN class="punctuation token">(</SPAN><SPAN class="string token">"category"</SPAN><SPAN class="punctuation token">)</SPAN><SPAN class="punctuation token">.</SPAN>innerHTML <SPAN class="operator token">=</SPAN> <SPAN class="string token">"Category "</SPAN> <SPAN class="operator token">+</SPAN> category<SPAN class="punctuation token">;</SPAN>
dom<SPAN class="punctuation token">.</SPAN><SPAN class="token function">byId</SPAN><SPAN class="punctuation token">(</SPAN><SPAN class="string token">"wind"</SPAN><SPAN class="punctuation token">)</SPAN><SPAN class="punctuation token">.</SPAN>innerHTML <SPAN class="operator token">=</SPAN> wind <SPAN class="operator token">+</SPAN> <SPAN class="string token">" kts"</SPAN><SPAN class="punctuation token">;</SPAN>
<SPAN class="comment token">// symbolize all line segments with the given</SPAN>
<SPAN class="comment token">// storm name with the same symbol</SPAN>
<SPAN class="keyword token">var</SPAN> renderer <SPAN class="operator token">=</SPAN> <SPAN class="keyword token">new</SPAN> <SPAN class="token class-name">UniqueValueRenderer</SPAN><SPAN class="punctuation token">(</SPAN><SPAN class="punctuation token">{</SPAN>
field<SPAN class="punctuation token">:</SPAN> <SPAN class="string token">"NAME"</SPAN><SPAN class="punctuation token">,</SPAN>
defaultSymbol<SPAN class="punctuation token">:</SPAN> layer<SPAN class="punctuation token">.</SPAN>renderer<SPAN class="punctuation token">.</SPAN>symbol <SPAN class="operator token">||</SPAN> layer<SPAN class="punctuation token">.</SPAN>renderer<SPAN class="punctuation token">.</SPAN>defaultSymbol<SPAN class="punctuation token">,</SPAN>
uniqueValueInfos<SPAN class="punctuation token">:</SPAN> <SPAN class="punctuation token">[</SPAN><SPAN class="punctuation token">{</SPAN>
value<SPAN class="punctuation token">:</SPAN> name<SPAN class="punctuation token">,</SPAN>
symbol<SPAN class="punctuation token">:</SPAN> <SPAN class="keyword token">new</SPAN> <SPAN class="token class-name">SimpleLineSymbol</SPAN><SPAN class="punctuation token">(</SPAN><SPAN class="punctuation token">{</SPAN>
color<SPAN class="punctuation token">:</SPAN> <SPAN class="string token">"orange"</SPAN><SPAN class="punctuation token">,</SPAN>
width<SPAN class="punctuation token">:</SPAN> <SPAN class="number token">5</SPAN><SPAN class="punctuation token">,</SPAN>
cap<SPAN class="punctuation token">:</SPAN> <SPAN class="string token">"round"</SPAN>
<SPAN class="punctuation token">}</SPAN><SPAN class="punctuation token">)</SPAN>
<SPAN class="punctuation token">}</SPAN><SPAN class="punctuation token">]</SPAN>
<SPAN class="punctuation token">}</SPAN><SPAN class="punctuation token">)</SPAN><SPAN class="punctuation token">;</SPAN>
layer<SPAN class="punctuation token">.</SPAN>renderer <SPAN class="operator token">=</SPAN> renderer<SPAN class="punctuation token">;</SPAN>
<SPAN class="punctuation token">}</SPAN><SPAN class="line-numbers-rows"><SPAN></SPAN><SPAN></SPAN><SPAN></SPAN><SPAN></SPAN><SPAN></SPAN><SPAN></SPAN><SPAN></SPAN><SPAN></SPAN><SPAN></SPAN><SPAN></SPAN><SPAN></SPAN><SPAN></SPAN><SPAN></SPAN><SPAN></SPAN><SPAN></SPAN><SPAN></SPAN><SPAN></SPAN><SPAN></SPAN><SPAN></SPAN><SPAN></SPAN><SPAN></SPAN><SPAN></SPAN><SPAN></SPAN><SPAN></SPAN><SPAN></SPAN><SPAN></SPAN><SPAN></SPAN><SPAN></SPAN><SPAN></SPAN></SPAN>In Chrome, it functions well... so, is this an issue with JSAPI v4 in IE11... is there a workaround?
Thanks!