When we implemented URLs for Django our nemesis was Vignette, a popular CMS at the time (~2003) which frequently included commas in long weird URLs.
It's hard to find an example
Of one of those now, because the kind of sites that tolerate weird comma-infested URLs in 2003 aren't the kind of sites that meticulously maintain those URLs in working order for 20+ years!
It's hard to find an example Of one of those now, because the kind of sites that tolerate weird comma-infested URLs in 2003 aren't the kind of sites that meticulously maintain those URLs in working order for 20+ years!