Percent encoding of space character (%20) in site URL

What steps will reproduce the problem?
1. Install to a MAMP subdirectory that includes a space character - e.g., `new 
folder`. The browser will encode the space so the URL becomes 
`localhost:8888/new%20folder/`. Install will be successful assuming you are 
tall enough to ride the roller coaster.
2. Note site URL in Preferences; Textpattern will display it without percent 
encoding - e.g., `localhost:8888/new folder`.
3. View site using View Site tab. It will open a new tab/window with 
`localhost:8888/new%20folder/` and throw a 404 error.
4. Switch site URL in Preferences to `localhost:8888/new%20folder`. View Site 
hyperlinks to `localhost:8888/new%20folder/` and site loads.

What is the expected output? What do you see instead?
I expect to see the site content. I get a 404.

What version of the product are you using? On what operating system?
4.5.5 on MAMP 3.0.5, OS X 10.9.4

Please provide any additional information below.
Background: http://forum.textpattern.com/viewtopic.php?id=41761
Video walkthrough with commentary: https://www.youtube.com/watch?v=3Ry6c4F-Ax0

Original issue reported on code.google.com by p...@pragmatika.net on 20 Jul 2014 at 9:01

bgarrels / textpattern

Percent encoding of space character (%20) in site URL #421