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HTML is good for debugging, but is unsuitable for application use.
Specify the format parameter to change the output format.
To see the non HTML representation of the XML format, set format=xml.
See the complete documentation, or API help for more information. 
<?xml version="1.0"?>
<api>
  <compare fromrevid="1" torevid="2" xml:space="preserve">&lt;tr&gt;&lt;td colspan=&quot;2&quot; class=&quot;diff-lineno&quot;&gt;Line 1:&lt;/td&gt;
&lt;td colspan=&quot;2&quot; class=&quot;diff-lineno&quot;&gt;Line 1:&lt;/td&gt;&lt;/tr&gt;
&lt;tr&gt;&lt;td class='diff-marker'&gt;−&lt;/td&gt;&lt;td class='diff-deletedline'&gt;&lt;div&gt;&lt;del class=&quot;diffchange diffchange-inline&quot;&gt;&amp;lt;big&amp;gt;'''Uppsetning á MediaWiki heppnaðist&lt;/del&gt;.&lt;del class=&quot;diffchange diffchange-inline&quot;&gt;'''&amp;lt;/big&amp;gt;&lt;/del&gt;&lt;/div&gt;&lt;/td&gt;&lt;td class='diff-marker'&gt;+&lt;/td&gt;&lt;td class='diff-addedline'&gt;&lt;div&gt;&lt;ins class=&quot;diffchange diffchange-inline&quot;&gt;A Noun Phrase (icel&lt;/ins&gt;. &lt;ins class=&quot;diffchange diffchange-inline&quot;&gt;nafnliður) is a phrase whose head is a noun&lt;/ins&gt;.&lt;/div&gt;&lt;/td&gt;&lt;/tr&gt;
&lt;tr&gt;&lt;td class='diff-marker'&gt;−&lt;/td&gt;&lt;td class='diff-deletedline'&gt;&lt;div&gt;&amp;#160;&lt;/div&gt;&lt;/td&gt;&lt;td class='diff-marker'&gt;+&lt;/td&gt;&lt;td class='diff-addedline'&gt;&lt;div&gt;&lt;/div&gt;&lt;/td&gt;&lt;/tr&gt;
&lt;tr&gt;&lt;td class='diff-marker'&gt;−&lt;/td&gt;&lt;td class='diff-deletedline'&gt;&lt;div&gt;&lt;del class=&quot;diffchange diffchange-inline&quot;&gt;Ráðfærðu þig við [http://meta&lt;/del&gt;.&lt;del class=&quot;diffchange diffchange-inline&quot;&gt;wikimedia.org/wiki/Help:Contents Notandahandbókina] fyrir frekari upplýsingar um notkun wiki-hugbúnaðarins.&lt;/del&gt;&lt;/div&gt;&lt;/td&gt;&lt;td class='diff-marker'&gt;+&lt;/td&gt;&lt;td class='diff-addedline'&gt;&lt;div&gt;&lt;/div&gt;&lt;/td&gt;&lt;/tr&gt;
&lt;tr&gt;&lt;td class='diff-marker'&gt;−&lt;/td&gt;&lt;td class='diff-deletedline'&gt;&lt;div&gt;&amp;#160;&lt;/div&gt;&lt;/td&gt;&lt;td class='diff-marker'&gt;+&lt;/td&gt;&lt;td class='diff-addedline'&gt;&lt;div&gt;&lt;/div&gt;&lt;/td&gt;&lt;/tr&gt;
&lt;tr&gt;&lt;td class='diff-marker'&gt;−&lt;/td&gt;&lt;td class='diff-deletedline'&gt;&lt;div&gt;&lt;del class=&quot;diffchange diffchange-inline&quot;&gt;== Fyrir byrjendur ==&lt;/del&gt;&lt;/div&gt;&lt;/td&gt;&lt;td class='diff-marker'&gt;+&lt;/td&gt;&lt;td class='diff-addedline'&gt;&lt;div&gt;&lt;/div&gt;&lt;/td&gt;&lt;/tr&gt;
&lt;tr&gt;&lt;td class='diff-marker'&gt;−&lt;/td&gt;&lt;td class='diff-deletedline'&gt;&lt;div&gt;&amp;#160;&lt;/div&gt;&lt;/td&gt;&lt;td class='diff-marker'&gt;+&lt;/td&gt;&lt;td class='diff-addedline'&gt;&lt;div&gt;&lt;/div&gt;&lt;/td&gt;&lt;/tr&gt;
&lt;tr&gt;&lt;td class='diff-marker'&gt;−&lt;/td&gt;&lt;td class='diff-deletedline'&gt;&lt;div&gt;&lt;del class=&quot;diffchange diffchange-inline&quot;&gt;* [http://www.mediawiki.org/wiki/Manual:Configuration_settings Listi yfir uppsetningarstillingar]&lt;/del&gt;&lt;/div&gt;&lt;/td&gt;&lt;td class='diff-marker'&gt;+&lt;/td&gt;&lt;td class='diff-addedline'&gt;&lt;div&gt;&lt;/div&gt;&lt;/td&gt;&lt;/tr&gt;
&lt;tr&gt;&lt;td class='diff-marker'&gt;−&lt;/td&gt;&lt;td class='diff-deletedline'&gt;&lt;div&gt;&lt;del class=&quot;diffchange diffchange-inline&quot;&gt;* [http://www.mediawiki.org/wiki/Manual:FAQ MediaWiki Algengar spurningar MediaWiki]&lt;/del&gt;&lt;/div&gt;&lt;/td&gt;&lt;td class='diff-marker'&gt;+&lt;/td&gt;&lt;td class='diff-addedline'&gt;&lt;div&gt;&lt;/div&gt;&lt;/td&gt;&lt;/tr&gt;
&lt;tr&gt;&lt;td class='diff-marker'&gt;−&lt;/td&gt;&lt;td class='diff-deletedline'&gt;&lt;div&gt;&lt;del class=&quot;diffchange diffchange-inline&quot;&gt;* [https://lists.wikimedia.org/mailman/listinfo/mediawiki-announce Póstlisti MediaWiki-útgáfa]&lt;/del&gt;&lt;/div&gt;&lt;/td&gt;&lt;td class='diff-marker'&gt;+&lt;/td&gt;&lt;td class='diff-addedline'&gt;&lt;div&gt;&lt;/div&gt;&lt;/td&gt;&lt;/tr&gt;
</compare>
</api>