Why Drupal won't remember "use search" permission settings for roles? I want to make search available to everyone who uses the site, including anonymous users.
Now, if i go to /admin/people/permissions and and try to enable "use search" for anonymous and authenticated users, the systems seems to act okay, but when I look at it again, nothing's changed. The settings seemingly won't remember my settings. 
Any ideas? I hope that there's something totally simple I forgot

EDIT: in fact, it does not keep any changes in the permission system.   

EDIT 2: I made it work by editing permissions through /admin/people/permissions/roles. Does anyone has any ideas why it was possible in one way but not the other?
PHP has a default setting of 1000 for max_input_vars, and once you have a significant number of modules and/or roles defined, you end up with an excess number of permissions boxes on the page. 

In your php.ini file add max_input_vars = 1500 and keep incrementally increasing it until it saves.