diff --git a/briar-android/src/main/java/org/briarproject/briar/android/conversation/AttachmentController.java b/briar-android/src/main/java/org/briarproject/briar/android/conversation/AttachmentController.java
index 7c4339c3e..a5d6ca146 100644
--- a/briar-android/src/main/java/org/briarproject/briar/android/conversation/AttachmentController.java
+++ b/briar-android/src/main/java/org/briarproject/briar/android/conversation/AttachmentController.java
@@ -175,10 +175,18 @@ class AttachmentController {
 		float widthPercentage = maxWidth / (float) width;
 		float heightPercentage = maxHeight / (float) height;
 		float scaleFactor = Math.min(widthPercentage, heightPercentage);
+		if (scaleFactor > 1) scaleFactor = 1f;
 		int thumbnailWidth = (int) (width * scaleFactor);
 		int thumbnailHeight = (int) (height * scaleFactor);
-		if (thumbnailWidth < minWidth) thumbnailWidth = minWidth;
-		if (thumbnailHeight < minHeight) thumbnailHeight = minHeight;
+		if (thumbnailWidth < minWidth || thumbnailHeight < minHeight) {
+			widthPercentage = minWidth / (float) width;
+			heightPercentage = minHeight / (float) height;
+			scaleFactor = Math.max(widthPercentage, heightPercentage);
+			thumbnailWidth = (int) (width * scaleFactor);
+			thumbnailHeight = (int) (height * scaleFactor);
+			if (thumbnailWidth > maxWidth) thumbnailWidth = maxWidth;
+			if (thumbnailHeight > maxHeight) thumbnailHeight = maxHeight;
+		}
 		return new Size(thumbnailWidth, thumbnailHeight);
 	}
 
diff --git a/briar-android/src/main/java/org/briarproject/briar/android/conversation/glide/BriarDataFetcher.java b/briar-android/src/main/java/org/briarproject/briar/android/conversation/glide/BriarDataFetcher.java
index 252e8df57..51d51434d 100644
--- a/briar-android/src/main/java/org/briarproject/briar/android/conversation/glide/BriarDataFetcher.java
+++ b/briar-android/src/main/java/org/briarproject/briar/android/conversation/glide/BriarDataFetcher.java
@@ -21,7 +21,6 @@ import java.util.logging.Logger;
 import javax.inject.Inject;
 
 import static com.bumptech.glide.load.DataSource.LOCAL;
-import static java.util.Objects.requireNonNull;
 import static java.util.logging.Level.WARNING;
 import static java.util.logging.Logger.getLogger;
 import static org.briarproject.bramble.util.LogUtils.logException;
@@ -52,7 +51,7 @@ class BriarDataFetcher implements DataFetcher<InputStream> {
 	@Override
 	public void loadData(Priority priority,
 			DataCallback<? super InputStream> callback) {
-		MessageId id = requireNonNull(attachment).getMessageId();
+		MessageId id = attachment.getMessageId();
 		dbExecutor.execute(() -> {
 			if (cancel) return;
 			try {