Why is the number of result columns displayed when applying a filter not fixed?

Some themes allow you to define the number of product columns displayed on pages of "product list" type but which are not "category" pages. 

When you are on a category page and you apply a filter thanks to our module, the results page is no longer seen by your theme as a category page and therefore the number of columns is equal to the one defined in your theme. To keep the same number of result columns as on category pages, you need to modify your theme (or ask your theme editor to do so) taking into account the result pages generated by our module.

For example, if your theme contains this condition to set the number of columns on pages that are not category pages:

{if $page_name !='category'}

 [...]

{/if}

Then the code must be modified to take into account the results pages generated by our module:

{if $page_name !='category' && $page_name !='module-pm_advancedsearch4-advancedsearch4' && $page_name !='module-pm_advancedsearch4-searchresults'}

 [...]

{/if}