By "not properly", I mean "not", apparently. Try this link, for example:
Steps to reproduce:
- Execute a query with a string parameter (e.g., this one) with spaces in it
- Switch the site by clicking on another site's icon
- Observe wrong parameter value
As you repeat this, the string "accept rate" becomes:
accept rate accept+rate accept%2Brate accept%252Brate
… and so on and so forth.