Why do I have problems displaying certain icons?

If you note a displaying issue for certain icons, such as the "+" between the products of a pack like below:

it's because your theme does not include the "Material Icons" library of the default theme, used to dispay this kind of icons.

Two solutions are possible to solve the problem:

• Manually include the library into the loaded ressources, in order to make the icones functional (see this documentation)
• Override the pack template in order to use a different icon, included in your theme for example