commit b36227cd90bc7c0f3b18cd46f09cb86f39e16ae6
Author: Leszek Koltunski <leszek@koltunski.pl>
Date:   Tue Sep 7 12:39:24 2021 +0200

    Minor.

diff --git a/src/main/java/org/distorted/library/main/InternalStackFrame.java b/src/main/java/org/distorted/library/main/InternalStackFrame.java
index abf8d63..c7d2be6 100644
--- a/src/main/java/org/distorted/library/main/InternalStackFrame.java
+++ b/src/main/java/org/distorted/library/main/InternalStackFrame.java
@@ -27,7 +27,7 @@ import java.util.LinkedList;
 
 ///////////////////////////////////////////////////////////////////////////////////////////////////
 /**
- * Implements a single 'frame' of all varaibles needed to remember the internal state of the library.
+ * Implements a single 'frame' of all variables needed to remember the internal state of the library.
  * Such a frame must be remembered in a list whenever current Activity using the library fires off
  * another Activity which also wants to use the library. When that happens, we create a new 'frame',
  * remember the old one. When the second Activity ends and we come back to the first, we destroy the
diff --git a/src/main/java/org/distorted/library/main/InternalStackFrameList.java b/src/main/java/org/distorted/library/main/InternalStackFrameList.java
index 889bb6a..b931457 100644
--- a/src/main/java/org/distorted/library/main/InternalStackFrameList.java
+++ b/src/main/java/org/distorted/library/main/InternalStackFrameList.java
@@ -23,7 +23,6 @@ import org.distorted.library.message.EffectMessageSender;
 
 import java.util.ArrayList;
 import java.util.HashMap;
-import java.util.Set;
 
 ///////////////////////////////////////////////////////////////////////////////////////////////////
 /**