bug: redirect loop when domain contains capitals

Thank you for this plugin, I always use it.

I think I found a bug, when mapping to a domain that contains capitals the site will keep redirecting to itself.

Example:
eXamPleDomaiN.com – redirect loop
exampledomain.com – works fine

Obvious workaround is to not enter the domain in capitals, but might be better if it validated this or just changed all domains to lowercase automatically?

https://ww.wp.xz.cn/plugins/wordpress-mu-domain-mapping/