Mixed case siteurl causes infinite loops on static front pages

[Clorith]

If your siteurl is set up using mixed case characters, and your site has pretty permalinks with a static home page set, this results in an infinite loop on the front page.

All actual posts and pages will still function as expected, only front pages will result in this loop.

Looks to have first been reported in #21602, but has worked since, to be re-introduced in 4.4.1

[Clorith]

Severity bump as it does leave front pages inaccesible

[azaozz]

Duplicate of #35353 and #35344.

[BLLuten]

Was this fixed in 4.4.2 and now it's a problem again in 4.5?

​https://wordpress.org/support/topic/read-this-first-wordpress-44-master-list?replies=7&view=all#post-7857957

Maybe I'm also seeing an issue where the web.config file on IIS is not being updated incorrectly.