diff --git a/koha-tmpl/opac-tmpl/bootstrap/en/modules/opac-opensearch.tt b/koha-tmpl/opac-tmpl/bootstrap/en/modules/opac-opensearch.tt
index d663d67b05..216aa5354b 100644
--- a/koha-tmpl/opac-tmpl/bootstrap/en/modules/opac-opensearch.tt
+++ b/koha-tmpl/opac-tmpl/bootstrap/en/modules/opac-opensearch.tt
@@ -38,7 +38,7 @@
      <opensearch:Query role="request" searchTerms="[% SEARCH_RESULT.query_desc |uri %][% SEARCH_RESULT.limit_desc |uri %]" startPage="[% SEARCH_RESULT.page | html %]" />
      <item>
        <title>[% SEARCH_RESULT.title | html %] [% FOREACH subtitl IN SEARCH_RESULT.subtitle %], [% subtitl.subfield | html %][% END %]</title>
-       <dc:identifier>ISBN [% SEARCH_RESULT.isbn | html %]</dc:identifier>
+       <dc:identifier>ISBN:[% SEARCH_RESULT.isbn | html %]</dc:identifier>
         [% IF ( SEARCH_RESULT.BiblioDefaultViewmarc ) %]
         <link>[% OPACBaseURL | url %]/cgi-bin/koha/opac-MARCdetail.pl?biblionumber=[% SEARCH_RESULT.biblionumber | uri %]</link>
         [% ELSIF ( SEARCH_RESULT.BiblioDefaultViewisbd ) %]
@@ -83,7 +83,7 @@
        xmlns:opensearch="http://a9.com/-/spec/opensearch/1.1/">
    <id>[% OPACBaseURL | url %]/cgi-bin/koha/opac-search.pl?[% query_cgi | html %][% limit_cgi | html %]&amp;format=atom</id>
    <title>[% LibraryName | html %] Search [% IF ( query_desc ) %]for '[% query_desc | html %]'[% END %][% IF ( limit_desc ) %]&nbsp;with limit(s):&nbsp;'[% limit_desc | html %]'[% END %]</title>
-    <link href="[% OPACBaseURL | url %]/cgi-bin/koha/opac-search.pl?[% query_cgi | html %][% limit_cgi | html %]&amp;format=rss2"/>
+    <link href="[% OPACBaseURL | url %]/cgi-bin/koha/opac-search.pl?[% query_cgi | html %][% limit_cgi | html %]&amp;format=rss"/>
    <updated>[% timestamp | html %]</updated>
    <author>
      <name>[% LibraryName | html %]</name>
diff --git a/opac/opac-search.pl b/opac/opac-search.pl
index 3886c35264..a027f04dc2 100755
--- a/opac/opac-search.pl
+++ b/opac/opac-search.pl
@@ -119,7 +119,7 @@ else {
     $template_type = 'advsearch';
 }
 
-$format = 'rss' if $format =~ /rss/;
+$format = 'rss' if $format =~ /^rss2?$/;
 
 # load the template
 ($template, $borrowernumber, $cookie) = get_template_and_user({