Categorization in the collection panel should treat characters such as œ specially

In the collection panel, no new category should be created for artists starting with œ, it should go with the other artists starting with o.
There is a whole list of such symbols.
strxfrm,strcoll,... use the file /usr/share/i18n/locales/iso14651_t1_common to define which symbols to expand, and how to.

The following command:
grep "\( \| \)\"<" /usr/share/i18n/locales/iso14651_t1_common | grep -v collating
outputs all these symbols in this form:
<U00E6> "<a><e>";"<LIG><LIG>";"<MIN><MIN>";IGNORE # 230 æ
which means that the unicode character 0x00E6 should be treated as 'a'.