When typing in the search bar, it is proposed to restrict the search to a sub-forum.
When selecting "International Français" the following info are added in the bar
#international:francais
This leads to a "no result" message
The inserted text should be as follows using a c with the cedilla
The search qualifier is composed of the combination of the "slug" of the category and its immediate parent category. With the previous slugs, this resulted both categories having the qualifier #international:francais. I have now fixed it by configuring a unique slug international-read-only for the Forum 2005-2010 (read only) > International category, meaning the established #international:francais qualifier is now unambiguous and will provide search results from the International > Français category as expected.
The same type of collision also previously existed for other "international" categories. The fix I made resolved it for all of them.
With forum's current settings, the only ASCII characters are allowed in the category "slug". This is the reason for the presence of the c character instead of ç in the search identifier.
It is possible to change the configuration to use "percent encoding" instead:
However, I haven't seen any complaints about the current "transliterated" slugs. I found the search stopped working when I tried it on the staging forum, and I'm not sure #international:fran%C3%A7ais is enough of an improvement over #international:francais anyway.