When there is no mobile theme provided with the current theme, the variable _PS_THEME_MOBILE_OVERRIDE_DIR_ is not defined. We so get the following error in apache logs:
"PHP Notice: Use of undefined constant _PS_THEME_MOBILE_OVERRIDE_DIR_ - assumed '_PS_THEME_MOBILE_OVERRIDE_DIR_' in FrontController.php"
When accessing the translation part with "core translation" , you got 2 errors:
Notice: Use of undefined constant _PS_THEME_SELECTED_DIR_ - assumed '_PS_THEME_SELECTED_DIR_' in controllers\admin\AdminTranslationsController.php on line 1018
Notice: Use of undefined constant _PS_THEME_SELECTED_DIR_ - assumed '_PS_THEME_SELECTED_DIR_' in \controllers\admin\AdminTranslationsController.php on line 1026
It's because the variable $this->theme_selected is not set for that case.
For module controller, make sure that the name of the controller and the module are saved in lowercase. Otherwise the route will not be found in getModuleLink.
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