Editing Magento (section)

====config.xml====
* optional
* <MODULE_ROOT_DIR>/etc/'''config.xml'''
* system configuration file ([https://devdocs.magento.com/guides/v2.3/config-guide/config/config-files.html official documentation])
* the default values of the attributes are somehow the 'reset to factory values', they are used if no corresponding XPath DB entry is found in  [[Magento#DB_Tables| table core_config_data]]
* if a module is deinstalled or the name or path is changed they have to be deleted manually from the DB

=====General=====
 <config>
   <default>
     [<section_id>|[[Magento#Carriers|<CARRIERS_SECTION>]] // see [[Magento#system.xml|system.xml]]
       <group_id> // see [[Magento#system.xml|system.xml]]
         <field_id>...</field_id> // see [[Magento#system.xml|system.xml]]
         ...
       </group_id>
     </section_id>]
     [[Magento#Carriers|<CARRIERS>]] 
   </default>
 </config>

=====Carriers=====
* A '''Carrier''' represents a shipping carrier, just like in real world (ex. FedEx).
* XPath (e.g. in table core_config_data) is carriers/<CODENAME>/<ATTRIBUTE>
 ...
 <default>
   <carriers> // carries is for shipping, other options ???
     <<CODENAME>>  // same as $_code property in model class
       <<CONFIG_ATTRIBUTE>><SYSTEM_DEFAULT_VALUE></<CONFIG_ATTRIBUTE>> // name used in [[Magento#system.xml|system.xml]] and in code
       <active><0|???></active> // mandatory, active or not
       <model>
         <FILEPATH_FILENAME_WO_EXT> // mandatory, model class with same name as FILENAME
       </model>
       <title><TEXT></title> // mandatory, displayed in the frontend as name of shipping carrier and in backend as title
       <sallowspecific><0|1></sallowspecific>   // mandatory, for carries: available in all countries or only in selected countries
       <sort_order></sort_order> // mandatory
       <name><TEXT></name> // optional, shown in frontend as name of shipping method and in backend as method
     </<CODENAME>>
   </carriers>
 </default>