diff --git a/src/main/kotlin/app/revanced/patches/reddit/customclients/redditisfun/api/fingerprints/AbstractClientIdFingerprint.kt b/src/main/kotlin/app/revanced/patches/reddit/customclients/redditisfun/api/fingerprints/AbstractClientIdFingerprint.kt
new file mode 100644
index 000000000..fe166b91d
--- /dev/null
+++ b/src/main/kotlin/app/revanced/patches/reddit/customclients/redditisfun/api/fingerprints/AbstractClientIdFingerprint.kt
@@ -0,0 +1,7 @@
+package app.revanced.patches.reddit.customclients.redditisfun.api.fingerprints
+
+import app.revanced.patcher.fingerprint.method.impl.MethodFingerprint
+
+abstract class AbstractClientIdFingerprint(string: String) : MethodFingerprint(
+    strings = listOfNotNull("yyOCBp.RHJhDKd", string),
+)
\ No newline at end of file
diff --git a/src/main/kotlin/app/revanced/patches/reddit/customclients/redditisfun/api/fingerprints/BasicAuthorizationFingerprint.kt b/src/main/kotlin/app/revanced/patches/reddit/customclients/redditisfun/api/fingerprints/BasicAuthorizationFingerprint.kt
new file mode 100644
index 000000000..9e4b3530a
--- /dev/null
+++ b/src/main/kotlin/app/revanced/patches/reddit/customclients/redditisfun/api/fingerprints/BasicAuthorizationFingerprint.kt
@@ -0,0 +1,5 @@
+package app.revanced.patches.reddit.customclients.redditisfun.api.fingerprints
+
+object BasicAuthorizationFingerprint : AbstractClientIdFingerprint(
+    string = "fJOxVwBUyo*=f:<OoejWs:AqmIJ", // Encrypted basic authorization string.
+)
\ No newline at end of file
diff --git a/src/main/kotlin/app/revanced/patches/reddit/customclients/redditisfun/api/fingerprints/BuildAuthorizationStringFingerprint.kt b/src/main/kotlin/app/revanced/patches/reddit/customclients/redditisfun/api/fingerprints/BuildAuthorizationStringFingerprint.kt
new file mode 100644
index 000000000..514a91ae3
--- /dev/null
+++ b/src/main/kotlin/app/revanced/patches/reddit/customclients/redditisfun/api/fingerprints/BuildAuthorizationStringFingerprint.kt
@@ -0,0 +1,5 @@
+package app.revanced.patches.reddit.customclients.redditisfun.api.fingerprints
+
+object BuildAuthorizationStringFingerprint : AbstractClientIdFingerprint(
+    string = "client_id"
+)
\ No newline at end of file
diff --git a/src/main/kotlin/app/revanced/patches/reddit/customclients/redditisfun/api/patch/ChangeOAuthClientIdPatch.kt b/src/main/kotlin/app/revanced/patches/reddit/customclients/redditisfun/api/patch/ChangeOAuthClientIdPatch.kt
new file mode 100644
index 000000000..f9ec75076
--- /dev/null
+++ b/src/main/kotlin/app/revanced/patches/reddit/customclients/redditisfun/api/patch/ChangeOAuthClientIdPatch.kt
@@ -0,0 +1,57 @@
+package app.revanced.patches.reddit.customclients.redditisfun.api.patch
+
+import app.revanced.patcher.annotation.Compatibility
+import app.revanced.patcher.annotation.Package
+import app.revanced.patcher.data.BytecodeContext
+import app.revanced.patcher.extensions.InstructionExtensions.getInstruction
+import app.revanced.patcher.extensions.InstructionExtensions.replaceInstruction
+import app.revanced.patcher.fingerprint.method.impl.MethodFingerprintResult
+import app.revanced.patcher.fingerprint.method.impl.MethodFingerprintResult.MethodFingerprintScanResult.StringsScanResult.StringMatch
+import app.revanced.patcher.patch.PatchResult
+import app.revanced.patcher.patch.PatchResultSuccess
+import app.revanced.patches.reddit.customclients.AbstractChangeOAuthClientIdPatch
+import app.revanced.patches.reddit.customclients.ChangeOAuthClientIdPatchAnnotation
+import app.revanced.patches.reddit.customclients.redditisfun.api.fingerprints.BasicAuthorizationFingerprint
+import app.revanced.patches.reddit.customclients.redditisfun.api.fingerprints.BuildAuthorizationStringFingerprint
+import org.jf.dexlib2.iface.instruction.OneRegisterInstruction
+
+@ChangeOAuthClientIdPatchAnnotation
+@Compatibility([Package("com.andrewshu.android.reddit")])
+class ChangeOAuthClientIdPatch : AbstractChangeOAuthClientIdPatch(
+    "redditisfun://auth",
+    Options,
+    listOf(
+        BuildAuthorizationStringFingerprint,
+        BasicAuthorizationFingerprint,
+    )
+) {
+    override fun List<MethodFingerprintResult>.patch(context: BytecodeContext): PatchResult {
+        /**
+         * Replaces a one register instruction with a const-string instruction
+         * at the index returned by [getReplacementIndex].
+         *
+         * @param string The string to replace the instruction with.
+         * @param getReplacementIndex A function that returns the index of the instruction to replace
+         * using the [StringMatch] list from the [MethodFingerprintResult].
+         */
+        fun MethodFingerprintResult.replaceWith(
+            string: String,
+            getReplacementIndex: List<StringMatch>.() -> Int,
+        ) = mutableMethod.apply {
+            val replacementIndex = scanResult.stringsScanResult!!.matches.getReplacementIndex()
+            val clientIdRegister = getInstruction<OneRegisterInstruction>(replacementIndex).registerA
+
+            replaceInstruction(replacementIndex, "const-string v$clientIdRegister, \"$string\"")
+        }
+
+        // Patch OAuth authorization.
+        first().replaceWith(clientId!!) { first().index + 4 }
+
+        // Path basic authorization.
+        last().replaceWith("$clientId:") { last().index + 7 }
+
+        return PatchResultSuccess()
+    }
+
+    companion object Options : AbstractChangeOAuthClientIdPatch.Options.ChangeOAuthClientIdOptionsContainer()
+}
\ No newline at end of file