Karam made an interesting discovery for Bug 10176 [1],

putting "use utf8;" on Search.pm fixes URL of facets (not

display well for me, but url works).

Digging a little I found that on line 574 of master Search.pm

there is a strange symbol (last between []). Seems to be an

inverted question mark. Karam saids that is Arabic one.

572:# Sanitize the link value : parenthesis, question and exclamation mark will cause errors with CCL

573-                                my $facet_link_value = $one_facet;

574-                                $facet_link_value =~ s/[()!?¡¿؟]/ /g;

575-

Question: this char is a typo? Was introduced on Bug 9183 [2]

'use utf8;' fixes the substitute, and the URLs.

Also removing that char gives the same effect (without 'use utf8:'