Cannot list pages using names with spaces

Steps to reproduce:

• create a nested page with AWM (or just a normal space) named "New Space"
• create a nested page with AWM (or just a normal space) named "NewSpace"
• select "Custom list of pages"
• select each space next to "List pages to commit" and click the button

Results:

• the page "New Space" displays no results
• the page "NewSpace" displays some results