diff --git a/Signal/src/ViewControllers/AttachmentApprovalViewController.swift b/Signal/src/ViewControllers/AttachmentApprovalViewController.swift
index 26e5000e6..c2b9dca99 100644
--- a/Signal/src/ViewControllers/AttachmentApprovalViewController.swift
+++ b/Signal/src/ViewControllers/AttachmentApprovalViewController.swift
@@ -183,7 +183,7 @@ class AttachmentApprovalViewController: UIViewController {
                 ? numberFormatter.string(from: NSNumber(value: fileSize / kOneKilobyte))! + " kb"
                 : numberFormatter.string(from: NSNumber(value: fileSize))!))
         fileSizeLabel.text = String(format:NSLocalizedString("ATTACHMENT_APPROVAL_FILE_SIZE_FORMAT",
-                                                             comment: "Format string for file size label in call interstitial view"),
+                                                             comment: "Format string for file size label in call interstitial view. Embeds: {{file size as 'N mb' or 'N kb'}}."),
                                     fileSizeText)
 
         fileSizeLabel.textColor = UIColor.white
diff --git a/Signal/src/ViewControllers/SignalAttachment.swift b/Signal/src/ViewControllers/SignalAttachment.swift
index dfe710ea9..6d48fecbe 100644
--- a/Signal/src/ViewControllers/SignalAttachment.swift
+++ b/Signal/src/ViewControllers/SignalAttachment.swift
@@ -126,7 +126,8 @@ class SignalAttachment: NSObject {
             do {
                 try data.write(to: fileUrl)
             } catch {
-                Logger.info("\(SignalAttachment.TAG) Could not write data to disk: \(dataUTI)")
+                Logger.error("\(SignalAttachment.TAG) Could not write data to disk: \(dataUTI)")
+                assertionFailure()
                 return nil
             }
             temporaryDataUrl = fileUrl