Note that R8 full mode should stay off for as long as possible.

E.g. retrofit requires new rules (not shipped yet), various Android X
libraries show stuff removed, my libraries maybe as well. Benefits are
low and risk and amount of work are high, so not doing this for now.

gradle.properties

@@ -14,4 +14,6 @@
 org.gradle.jvmargs=-Xmx1536M -Dkotlin.daemon.jvm.options\="-Xmx1536M"
 
 android.useAndroidX=true
+# Do not turn on full mode for as long as possible: looking at unused.txt diff there are many
+# differences with an increased risk of breaking things.
 android.enableR8.fullMode=false