when trying to install the german language pack from the repository I've got the error message about incompatible addon within iceape-uxp. The reason? The included file install.rdf within the XPI-package has the wrong version. The correction:
<?xml version="1.0"?>
<!--
-->
<RDF xmlns="http://www.w3.org/1999/02/22-rdf-syntax-ns#"
xmlns:em="http://www.mozilla.org/2004/em-rdf#">
<Description about="urn:mozilla:install-manifest"
em:id="langpack-de@iceape-uxp.hyperbola.info"
em:name="Deutsch (DE) Language Pack"
em:version="52.9.20181107"
em:type="8"
em:creator="Robert Kaiser">
<em:contributor>Abdulkadir Topal</em:contributor> <em:contributor>Alexander Ihrig</em:contributor> <em:contributor>Michael Opitz</em:contributor>
<em:targetApplication>
<Description>
<em:id>{9184b6fe-4a5c-484d-8b4b-efbfccbfb514}</em:id>
<em:minVersion>52.9.4</em:minVersion>
<em:maxVersion>52.9.*</em:maxVersion>
</Description>
</em:targetApplication>
</Description>
</RDF>Of course you need to add the modified file afterwards within the XPI-package. Just noting, perhaps this could be corrected within the official repositories?
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