If I call
https://xxxxx/api/products?display=full
It returns an error on PHP 7.4 (on PHP 7.3 works fine)
<prestashop xmlns:xlink="http://www.w3.org/1999/xlink">
<errors>
<error>
<code>
<![CDATA[ 5 ]]>
</code>
<message>
<![CDATA[ Trying to access array offset on value of type bool (C:\Aplicacions\prestashop.librofotos\classes\Product.php, line 7395) ]]>
</message>
</error>
<error>
<code>
<![CDATA[ 5 ]]>
</code>
<message>
<![CDATA[ [PHP Notice #8] Trying to access array offset on value of type bool (C:\Aplicacions\prestashop.librofotos\classes\Product.php, line 7395) ]]>
</message>
</error>
</errors>
</prestashop>