Falied to load resource files of Oracle APEX plugin
After APEX upgrade from one version to another you should recompile i.war by running java -jar ords.war validate --database apex. java -jar ords.war static could also be useful.

For debug it is convinient to edit ORDS config file defaults.xml with these strings:

&lt;entry key="debug.debugger"&gt;true&lt;/entry&gt;
&lt;entry key="debug.printDebugToScreen"&gt;true&lt;/entry&gt;


Don't forget to set them false on production.