My setup:
Drupal 7.2
Views 7.x-3.0-rc1
If I create a view with an exposed select widget with multiple selection enabled, I get a URL like this when when I select several options in the list and click Apply:
http://www.blahblah.com/viewname?field_select_value[]=2&field_select_val...
If I try to copy/paste this URL into the path of a custom menu item, it gets wrongly URL encoded upon save. In particular, note how all but the last value for field_select_value[] is lost.
viewname?field_select_value%5B%5D=5&=Apply
This encoding appears to happen repeatedly, such that path URL of the menu becomes further munged if I edit and save it again, w/o making any changes:
viewname?field_select_value%255B%255D=5&=Apply
And on the 2nd iteration:
viewname?field_select_value%25255B%25255D=5&=Apply
I gather this imperfect URL encoding would interfere in other instances of users wanting to create custom menu paths with query string parameters.