diff --git a/RELEASENOTES.md b/RELEASENOTES.md
index 9404a11342..8ef1c7e5eb 100644
--- a/RELEASENOTES.md
+++ b/RELEASENOTES.md
@@ -7,6 +7,9 @@
 *   Data sources:
     *   Add support for `android.resource` URI scheme in `RawResourceDataSource`
         ([#7866](https://github.com/google/ExoPlayer/issues/7866)).
+*   Core library:
+    *   Suppress Guava-related ProGuard/R8 warnings
+        ([#7904](https://github.com/google/ExoPlayer/issues/7904)).
 
 ### 2.12.0 (2020-09-11) ###
 
diff --git a/library/common/proguard-rules.txt b/library/common/proguard-rules.txt
index c83dbaee2d..18e5264c20 100644
--- a/library/common/proguard-rules.txt
+++ b/library/common/proguard-rules.txt
@@ -4,3 +4,6 @@
 -dontwarn org.checkerframework.**
 -dontwarn kotlin.annotations.jvm.**
 -dontwarn javax.annotation.**
+
+# From https://github.com/google/guava/wiki/UsingProGuardWithGuava
+-dontwarn java.lang.ClassValue
diff --git a/library/core/proguard-rules.txt b/library/core/proguard-rules.txt
index c599a93e5a..67c33679cd 100644
--- a/library/core/proguard-rules.txt
+++ b/library/core/proguard-rules.txt
@@ -75,8 +75,3 @@
 -keepclasseswithmembers class com.google.android.exoplayer2.source.smoothstreaming.SsMediaSource$Factory {
   <init>(com.google.android.exoplayer2.upstream.DataSource$Factory);
 }
-
-# Don't warn about checkerframework and Kotlin annotations
--dontwarn org.checkerframework.**
--dontwarn kotlin.annotations.jvm.**
--dontwarn javax.annotation.**