How do you show more than 8 columns in article list?

Only 8 columns show in the article list. The rest are display none in the CSS. 

I can select the columns to show dropdown, and choose the extra ones, but it does not remember that on save. 

So how do I change the default number of columns please? 

Thanks

hello can you be more precise ? where (backend front end ?)
some screen maybe ?

Sorry... I'm not at the computer at the moment so can't take a screenshot

in the backend I created a new Type for Products.

I then add lots of custom fields like price, image, stock and a lot more.

In the Configuration for it I enter the names of columns to show in the admin table.

If I go to Articles it shows all the articles created and there's a tab to show products.

I click products to see just those.

I can see only some of the custom fields in the columns. It only shows 8 columns. Extra custom fields I added are hidden.

I can click to show more fields in the column selector, but it does not remember that on page reload.

How can I permanently show all columns I added?

.

Hello about number of column i not sure that limited
About display column its linked to filtres type (tab in item liste)

In the file

administrator/components/com_flexicontent/views/items/tmpl/default.php

its this code hiding them:

style="<?php echo $this->hideCol($colposition++); ?>"

BUT I think its also in Javascript too, because even deleting these lines you see a flash of the columns, which then get hidden by JS.

So where is the code that sets the columns to 8?

I think its a problem with saving the cookies in column chooser. If I delete the cookie fc_columnchooser, then ALL columns come back.

When I use the dropdown to select columns, it does not save it. When I refresh the page ALL columns come back. The cookie fc_columnchooser does not change to reflect the new columns I chose.