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Drupal 8 - Media - File Media Type - Navigate to Manage Fields

1. Navigate to File Media Type Manage Fields

Go to Admin Menu > Structure > Media Types > File > Manage Fields.

Drupal 8 - Media - File Media Type - Manage Fields Overview

2. Manage Fields Tab Overview

The Manage Fields tab for the File media type currently has the single File field listed.

Drupal 8 - Media - File Media Type - Click File Field Edit Button

3. Edit File Field Settings

To edit the settings in the File field, click its corresponding Edit button.

Drupal 8 - Media - File Media Type - File Field Settings Overview

4. File Field Settings Overview

The default settings should work for most sites:

Label field = leave as is

Help Text field = add some additional help text if desired

Required Field checkbox = leave this as is

Allowed File Extensions field = contains many common document file extensions

File Directory field = uses tokens to automatically sort files into directories based on the year and month of upload

Maximum Upload Size field = enter a value if you want to limit the max upload size - leaving it blank will force it to use the system's maximum file upload size

Enable Description Field checkbox = leave as is - this provides the ability to add some descriptive information about the file, which can help with SEO

If any changes have been made, click the Save Settings button to save them.