diff --git a/app/proguard-rules.pro b/app/proguard-rules.pro
index a53f59c5a..e396b8a1b 100644
--- a/app/proguard-rules.pro
+++ b/app/proguard-rules.pro
@@ -23,3 +23,9 @@
 # Disable obfuscation completely for BCR. As an open source project,
 # shrinking is the only goal of minification.
 -dontobfuscate
+
+# We construct TreeDocumentFile via reflection in DocumentFileExtensions
+# to speed up SAF performance when doing path lookups.
+-keepclassmembers class androidx.documentfile.provider.TreeDocumentFile {
+    <init>(androidx.documentfile.provider.DocumentFile, android.content.Context, android.net.Uri);
+}