When visiting the field formatter page for an Icon field, the following error is thrown if the ui_icons_font is not enabled:
Drupal\Component\Plugin\Exception\PluginNotFoundException: The "font" plugin does not exist. Valid plugin IDs for Drupal\ui_icons_backport\IconExtractorPluginManager are: svg, path, svg_sprite in Drupal\Core\Plugin\DefaultPluginManager->doGetDefinition() (line 53 of core/lib/Drupal/Component/Plugin/Discovery/DiscoveryTrait.php).
Active
1.0
Code
Do you use the font extractor in one of your icon pack definition? If yes, you need ui_icons_font module. If not, let's investigate.
Automatically closed - issue fixed for 2 weeks with no activity.