Dynamic generated dropdown value is not passed to controller after page refresh.

if filterProducts dropdown is being generated dynamically then jQuery may not have access to it to detect the change event. Try changing the first line from

Code:

$('#filterProducts').on('change', function(b) {

to

Code:

$('body').on('change', '#filterProducts', function(b) {

$('#filterProducts') is the form which contains the dropdowns. I detect change events and then i generate the results in the main body. 
The two dropdowns are "#category" and the dynamically generated one, "#size".

If you have any better approach as for how to filter the data then feel free to tell!

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