[wordpress] Remove category & tag base from WordPress url - without a plugin

The non-category plugin did not work for me.

For Multisite WordPress the following works:

  1. Go to network admin sites;
  2. Open site under \;
  3. Go to settings;
  4. Under permalinks structure type /%category%/%postname%/. This will display your url as www.domainname.com/categoryname/postname;
  5. Now go to your site dashboard (not network dashboard);
  6. Open settings;
  7. Open permalink. Do not save (the permalink will show uneditable field as yourdoamainname/blog/. Ignore it. If you save now the work you did in step 4 will be overwritten. This step of opening permalink page but not saving in needed to update the database.