NullPointerException in Settings.<init>

Version 226.
Samsung Galaxy Note9 (crownlte), 5632MB RAM, Android 9:
```
java.lang.ExceptionInInitializerError:
at fr.gaulupeau.apps.Poche.App.getSettings (App.java:30)
at fr.gaulupeau.apps.Poche.ui.Themes.init (Themes.java:24)
at fr.gaulupeau.apps.Poche.ui.Themes. (Themes.java:20)
at fr.gaulupeau.apps.Poche.ui.MainActivity.onCreate (MainActivity.java:119)
at android.app.Activity.performCreate (Activity.java:7326)
at android.app.Activity.performCreate (Activity.java:7317)
at android.app.Instrumentation.callActivityOnCreate (Instrumentation.java:1271)
at android.app.ActivityThread.performLaunchActivity (ActivityThread.java:3072)
at android.app.ActivityThread.handleLaunchActivity (ActivityThread.java:3235)
at android.app.servertransaction.LaunchActivityItem.execute (LaunchActivityItem.java:78)
at android.app.servertransaction.TransactionExecutor.executeCallbacks (TransactionExecutor.java:108)
at android.app.servertransaction.TransactionExecutor.execute (TransactionExecutor.java:68)
at android.app.ActivityThread$H.handleMessage (ActivityThread.java:1926)
at android.os.Handler.dispatchMessage (Handler.java:106)
at android.os.Looper.loop (Looper.java:214)
at android.app.ActivityThread.main (ActivityThread.java:6990)
at java.lang.reflect.Method.invoke (Native Method)
at com.android.internal.os.RuntimeInit$MethodAndArgsCaller.run (RuntimeInit.java:493)
at com.android.internal.os.ZygoteInit.main (ZygoteInit.java:1445)
Caused by: java.lang.NullPointerException:
at fr.gaulupeau.apps.Poche.data.Settings. (Settings.java:68)
at fr.gaulupeau.apps.Poche.App$SettingsHolder.createSettings (App.java:18)
at fr.gaulupeau.apps.Poche.App$SettingsHolder. (App.java:15)
```
One report.