If it’s a feature and not a bug, place this at the top of your file.
/*jshint sub:true*/
If it’s a bug, you should refactor your code
foo['tracker'] = bar // from this...
foo.tracker = bar; // to this!
Good post on the reasons here: https://stackoverflow.com/a/2001410/94668
As suggested by: @ThorSummoner you can use below in your .jshintrc file
"sub": true