Don't back up profile pics, attachments or gifs.

// FREEBIE

Signal/src/Profiles/OWSProfileManager.m

@@ -1408,6 +1408,16 @@ const NSUInteger kOWSProfileManager_MaxAvatarDiameter = 640;
                 DDLogError(@"Failed to create profile avatars directory: %@", error);
             }
         }
+
+        NSURL *dirURL = [NSURL fileURLWithPath:profileAvatarsDirPath];
+        NSError *error = nil;
+        [dirURL setResourceValues:@{
+            NSURLIsExcludedFromBackupKey : @(YES),
+        }
+                            error:&error];
+        if (error) {
+            OWSFail(@"Failed to exclude profile avatars directory from backup: %@", error);
+        }
     });
     return profileAvatarsDirPath;
 }

Signal/src/network/GiphyDownloader.swift

@@ -842,6 +842,12 @@ extension URLSessionTask {
                                                 attributes:nil)
                 gifFolderPath = dirPath
             }
+
+            // Don't back up Giphy downloads.
+            var dirURL = NSURL.fileURL(withPath:dirPath)
+            var resourceValues = URLResourceValues()
+            resourceValues.isExcludedFromBackup = true
+            try dirURL.setResourceValues(resourceValues)
         } catch let error as NSError {
             owsFail("\(GiphyAsset.TAG) ensureTempFolder failed: \(dirPath), \(error)")
             gifFolderPath = tempDirPath

SignalServiceKit/src/Messages/Attachments/TSAttachmentStream.m

@@ -204,6 +204,16 @@ NS_ASSUME_NONNULL_BEGIN
                 DDLogError(@"Failed to create attachments directory: %@", error);
             }
         }
+
+        NSURL *dirURL = [NSURL fileURLWithPath:attachmentsFolder];
+        NSError *error = nil;
+        [dirURL setResourceValues:@{
+            NSURLIsExcludedFromBackupKey : @(YES),
+        }
+                            error:&error];
+        if (error) {
+            OWSFail(@"Failed to exclude attachments directory from backup: %@", error);
+        }
     });
     return attachmentsFolder;
 }