fix #256: transparent holes in advanced tabs

app/src/main/res/layout/advanced_settings.xml

@@ -3,7 +3,7 @@
     xmlns:android="http://schemas.android.com/apk/res/android"
     xmlns:app="http://schemas.android.com/apk/res-auto"
     android:layout_width="match_parent"
-    android:layout_height="match_parent"
+    android:layout_height="match_parent" android:background="#FFFFFF"
     >
 
     <com.google.android.material.textfield.TextInputLayout

app/src/main/res/layout/debug_fragment.xml

@@ -4,6 +4,7 @@
     xmlns:tools="http://schemas.android.com/tools"
     android:layout_width="match_parent"
     android:layout_height="match_parent"
+    android:background="#FFFFFF"
     >
 
     <androidx.recyclerview.widget.RecyclerView

build.gradle

@@ -21,7 +21,7 @@ buildscript {
         // Check that you have the Google Services Gradle plugin v4.3.2 or later
         // (if not, add it).
         classpath 'com.google.gms:google-services:4.3.5'
-        classpath 'com.google.firebase:firebase-crashlytics-gradle:2.5.0'
+        classpath 'com.google.firebase:firebase-crashlytics-gradle:2.5.1'
 
         // protobuf plugin - docs here https://github.com/google/protobuf-gradle-plugin
         classpath 'com.google.protobuf:protobuf-gradle-plugin:0.8.15'