Hello, Problem may also come module that adds tabs in the product sheet..!
Slider put the images in JPEG not in PNG
Other problem
Problem with the scrollTo () function on Google Chrome For Firefox also - Prestashop 1.6
The jQuery scrollTo () function is used by some Prestashop themes and modules to scroll to a specific place on the page.
However, I have seen since the release of Prestashop 1.6 that this feature posed some problems with Google Chrome, Firefox . This feature is handled by Prestashop's jquery.scrollTo plugin, but this plugin is not up-to-date in versions below Prestashop version 1.6.0.9, and this seems to be a problem with Google Chrome, Firefox. The solution is simply to update this plugin.
The problem with scrollTo () Google Chrome, Firefox, on features of certain themes and modules.
The problem can thus arise with the link "More details" present in the product sheets. The click on this link remains ineffective while it should scroll the page on the detailed description of the product.
The concern can also arise when opening the detail of a command in the client account, since the scroll on the detail of the open command does not occur.
Update plugin jquery.scrollTo
To do this, you must open the jquery.scrollTo.js file that is located in the js >> jquery >> plugins folder in your Prestashop store and replace its contents with it