Editorial: web compatibility typically remains relevant

Fixes #210.

dom.bs

@@ -2098,9 +2098,8 @@ steps:
 
 <h4 id=interface-nonelementparentnode>Mixin {{NonElementParentNode}}</h4>
 
-<p class="note no-backref">The {{NonElementParentNode/getElementById()}} method is not on
-<a for="/">elements</a> for compatibility with older versions of jQuery. If a time comes where that
-version of jQuery has disappeared, we might be able to support it.
+<p class="note no-backref">Web compatibility prevents the {{NonElementParentNode/getElementById()}}
+method from being exposed on <a for="/">elements</a> (and therefore on {{ParentNode}}).
 
 <pre class=idl>
 [NoInterfaceObject,
@@ -2313,9 +2312,9 @@ running <a>scope-match a selectors string</a> <var>selectors</var> against the
 
 <h4 id=interface-nondocumenttypechildnode>Mixin {{NonDocumentTypeChildNode}}</h4>
 
-<p class="note no-backref">The {{previousElementSibling}} and {{nextElementSibling}} attributes have
-been removed from {{DocumentType}} nodes for compatibility reasons. If these additions are deemed
-compatible enough in the future, they could be reinstated.
+<p class="note no-backref">Web compatibility prevents the {{previousElementSibling}} and
+{{nextElementSibling}} attributes from being exposed on <a for=/>doctypes</a> (and therefore on
+{{ChildNode}}).
 
 <pre class=idl>
 [NoInterfaceObject,
@@ -9733,6 +9732,7 @@ Tobie Langel,
 Tom Pixley,
 Travis Leithead,
 <i>triple-underscore</i>,<!--GitHub-->
+Veli Senol,
 Vidur Apparao,
 Warren He,
 Yehuda Katz,

dom.html

@@ -1319,8 +1319,7 @@ <h4 class="heading settled" data-level="4.2.3" id="mutation-algorithms"><span cl
  nextSibling <var>oldNextSibling</var>, and previousSibling <var>oldPreviousSibling</var>. 
    </ol>
    <h4 class="heading settled" data-level="4.2.4" id="interface-nonelementparentnode"><span class="secno">4.2.4. </span><span class="content">Mixin <code class="idl"><a data-link-type="idl" href="#nonelementparentnode">NonElementParentNode</a></code></span><a class="self-link" href="#interface-nonelementparentnode"></a></h4>
-   <p class="note no-backref" role="note">The <code class="idl"><a data-link-type="idl" href="#dom-nonelementparentnode-getelementbyid">getElementById()</a></code> method is not on <a data-link-type="dfn" href="#concept-element">elements</a> for compatibility with older versions of jQuery. If a time comes where that
-version of jQuery has disappeared, we might be able to support it. </p>
+   <p class="note no-backref" role="note">Web compatibility prevents the <code class="idl"><a data-link-type="idl" href="#dom-nonelementparentnode-getelementbyid">getElementById()</a></code> method from being exposed on <a data-link-type="dfn" href="#concept-element">elements</a> (and therefore on <code class="idl"><a data-link-type="idl" href="#parentnode">ParentNode</a></code>). </p>
 <pre class="idl def">[NoInterfaceObject,
  Exposed=Window]
 interface <dfn class="idl-code" data-dfn-type="interface" data-export="" id="nonelementparentnode">NonElementParentNode<a class="self-link" href="#nonelementparentnode"></a></dfn> {
@@ -1420,9 +1419,7 @@ <h4 class="heading settled" data-level="4.2.6" id="interface-parentnode"><span c
    <p>The <dfn class="idl-code" data-dfn-for="ParentNode" data-dfn-type="method" data-export="" id="dom-parentnode-queryselectorall"><code>querySelectorAll(<var>selectors</var>)</code><a class="self-link" href="#dom-parentnode-queryselectorall"></a></dfn> method, when invoked, must return the <a data-link-type="dfn" href="#concept-collection-static">static</a> result of
 running <a data-link-type="dfn" href="#scope-match-a-selectors-string">scope-match a selectors string</a> <var>selectors</var> against the <a data-link-type="dfn" href="#context-object">context object</a>.</p>
    <h4 class="heading settled" data-level="4.2.7" id="interface-nondocumenttypechildnode"><span class="secno">4.2.7. </span><span class="content">Mixin <code class="idl"><a data-link-type="idl" href="#nondocumenttypechildnode">NonDocumentTypeChildNode</a></code></span><a class="self-link" href="#interface-nondocumenttypechildnode"></a></h4>
-   <p class="note no-backref" role="note">The <code class="idl"><a data-link-type="idl" href="#dom-nondocumenttypechildnode-previouselementsibling">previousElementSibling</a></code> and <code class="idl"><a data-link-type="idl" href="#dom-nondocumenttypechildnode-nextelementsibling">nextElementSibling</a></code> attributes have
-been removed from <code class="idl"><a data-link-type="idl" href="#documenttype">DocumentType</a></code> nodes for compatibility reasons. If these additions are deemed
-compatible enough in the future, they could be reinstated. </p>
+   <p class="note no-backref" role="note">Web compatibility prevents the <code class="idl"><a data-link-type="idl" href="#dom-nondocumenttypechildnode-previouselementsibling">previousElementSibling</a></code> and <code class="idl"><a data-link-type="idl" href="#dom-nondocumenttypechildnode-nextelementsibling">nextElementSibling</a></code> attributes from being exposed on <a data-link-type="dfn" href="#concept-doctype">doctypes</a> (and therefore on <code class="idl"><a data-link-type="idl" href="#childnode">ChildNode</a></code>). </p>
 <pre class="idl def">[NoInterfaceObject,
  Exposed=Window]
 interface <dfn class="idl-code" data-dfn-type="interface" data-export="" id="nondocumenttypechildnode">NonDocumentTypeChildNode<a class="self-link" href="#nondocumenttypechildnode"></a></dfn> {
@@ -5124,6 +5121,7 @@ <h2 class="no-num heading settled" id="acks"><span class="content">Acknowledgmen
 Tobie Langel,
 Tom Pixley,
 Travis Leithead, <i>triple-underscore</i>,
+Veli Senol,
 Vidur Apparao,
 Warren He,
 Yehuda Katz,