diff --git a/backend/app/models/post.rb b/backend/app/models/post.rb
index a812fe5..589961f 100644
--- a/backend/app/models/post.rb
+++ b/backend/app/models/post.rb
@@ -226,12 +226,14 @@ class Post < ApplicationRecord
   end
 
   def self.sanitised_svg_bytes(bytes)
+    parse_options =
+        Nokogiri::XML::ParseOptions::STRICT |
+        Nokogiri::XML::ParseOptions::NONET
     document = Nokogiri::XML(
         bytes,
         nil,
         nil,
-        Nokogiri::XML::ParseOptions::STRICT
-        | Nokogiri::XML::ParseOptions::NONET)
+        parse_options)
     root = document.root
     raise MiniMagick::Error, 'SVG が不正です．' if root == nil || root.name != 'svg'
     raise MiniMagick::Error, 'SVG が不正です．' if document.internal_subset != nil
diff --git a/frontend/src/pages/posts/PostImportReviewPage.tsx b/frontend/src/pages/posts/PostImportReviewPage.tsx
index b3e71ce..e02f410 100644
--- a/frontend/src/pages/posts/PostImportReviewPage.tsx
+++ b/frontend/src/pages/posts/PostImportReviewPage.tsx
@@ -427,7 +427,8 @@ const PostImportReviewPage: FC<Props> = ({ user }) => {
 	: { duration: .2, ease: 'easeOut' as const }
 
   const [session, setSession] = useState<PostImportSession | null> (null)
-  const [loading, setLoading] = useState (false)
+  const [metadataLoading, setMetadataLoading] = useState (false)
+  const [submitting, setSubmitting] = useState (false)
   const [loadingRow, setLoadingRow] = useState<number | null> (null)
   const [editingRow, setEditingRow] = useState<PostImportRow | null> (null)
   const [showExistingRows, setShowExistingRows] = useState (false)
@@ -490,101 +491,106 @@ const PostImportReviewPage: FC<Props> = ({ user }) => {
       }
 
     const refreshRows = async (baseSession: PostImportSession) => {
-      setLoading (true)
-      let nextIndex = 0
-      const previewErrors = new Map<number, Record<string, string[]>> ()
-      let workingRows = [...(sessionRef.current ?? baseSession).rows]
+      if (active)
+	setMetadataLoading (true)
+      try
+      {
+        let nextIndex = 0
+        const previewErrors = new Map<number, Record<string, string[]>> ()
+        let workingRows = [...(sessionRef.current ?? baseSession).rows]
 
-      const mergeWorkingRow = (
-	  sourceRow: number,
-	  updater:   (row: PostImportRow) => PostImportRow,
-      ) => {
-	  workingRows = workingRows.map (row =>
-	      row.sourceRow === sourceRow
-	      ? updater (row)
-	      : row)
-	  const nextSession = buildSession (workingRows)
-	  sessionRef.current = nextSession
-	  setSession (nextSession)
-      }
-      const worker = async () => {
-        while (active)
-        {
-          const index = nextIndex
-          ++nextIndex
-          if (index >= baseSession.rows.length)
-            return
+        const mergeWorkingRow = (
+	    sourceRow: number,
+	    updater:   (row: PostImportRow) => PostImportRow,
+        ) => {
+	    workingRows = workingRows.map (row =>
+	        row.sourceRow === sourceRow
+	        ? updater (row)
+	        : row)
+	    const nextSession = buildSession (workingRows)
+	    sessionRef.current = nextSession
+	    setSession (nextSession)
+        }
+        const worker = async () => {
+          while (active)
+          {
+            const index = nextIndex
+            ++nextIndex
+            if (index >= baseSession.rows.length)
+              return
 
-          const baseRow = baseSession.rows[index]
-          if (baseRow.skipReason === 'manual'
-              || baseRow.importStatus === 'created'
-              || baseRow.importStatus === 'skipped'
-              || isNonRecoverableFailedRow (baseRow)
-              || baseRow.metadataUrl != null)
-            continue
-          const controller = new AbortController ()
-          controllers.add (controller)
-          try
-          {
-            const preview = await apiGet<PostMetadataResponse> ('/posts/metadata', {
-                params: { url: baseRow.url },
-                signal: controller.signal })
-            if (!(active) || previewSequenceRef.current !== previewSequence)
-              return
-            mergeWorkingRow (baseRow.sourceRow, row => mergePreviewRow (row, preview))
-          }
-          catch (requestError)
-          {
-            if (controller.signal.aborted)
-              return
-            if (!(active) || previewSequenceRef.current !== previewSequence)
-              return
-            if (!(isApiError<{
-		    errors?: Record<string, string[]>
-		    baseErrors?: string[]
-		}> (requestError)))
+            const baseRow = baseSession.rows[index]
+            if (baseRow.skipReason === 'manual'
+                || baseRow.importStatus === 'created'
+                || baseRow.importStatus === 'skipped'
+                || isNonRecoverableFailedRow (baseRow)
+                || baseRow.metadataUrl != null)
               continue
-            if (requestError.response?.status === 422)
-              {
-                const rowErrors = {
-		    ...(requestError.response.data.errors ?? { }),
-		    ...(requestError.response.data.baseErrors?.length
-			? {
-			    base: requestError.response.data.baseErrors }
-			: { }) }
-                previewErrors.set (baseRow.sourceRow, rowErrors)
-                mergeWorkingRow (baseRow.sourceRow, row => ({
-                    ...row,
-                    validationErrors: rowErrors,
-                    status: 'error' }))
-              }
-          }
-          finally
-          {
-            controllers.delete (controller)
+            const controller = new AbortController ()
+            controllers.add (controller)
+            try
+            {
+              const preview = await apiGet<PostMetadataResponse> ('/posts/metadata', {
+                  params: { url: baseRow.url },
+                  signal: controller.signal })
+              if (!(active) || previewSequenceRef.current !== previewSequence)
+                return
+              mergeWorkingRow (baseRow.sourceRow, row => mergePreviewRow (row, preview))
+            }
+            catch (requestError)
+            {
+              if (controller.signal.aborted)
+                return
+              if (!(active) || previewSequenceRef.current !== previewSequence)
+                return
+              if (!(isApiError<{
+		      errors?: Record<string, string[]>
+		      baseErrors?: string[]
+		  }> (requestError)))
+                continue
+              if (requestError.response?.status === 422)
+                {
+                  const rowErrors = {
+		      ...(requestError.response.data.errors ?? { }),
+		      ...(requestError.response.data.baseErrors?.length
+			  ? {
+			      base: requestError.response.data.baseErrors }
+			  : { }) }
+                  previewErrors.set (baseRow.sourceRow, rowErrors)
+                  mergeWorkingRow (baseRow.sourceRow, row => ({
+                      ...row,
+                      validationErrors: rowErrors,
+                      status: 'error' }))
+                }
+            }
+            finally
+            {
+              controllers.delete (controller)
+            }
           }
         }
-      }
 
-      await Promise.all (
-          Array.from ({ length: Math.min (4, baseSession.rows.length) }, () => worker ()))
-      if (!(active) || previewSequenceRef.current !== previewSequence)
-        {
-          setLoading (false)
+        await Promise.all (
+            Array.from ({ length: Math.min (4, baseSession.rows.length) }, () => worker ()))
+        if (!(active) || previewSequenceRef.current !== previewSequence)
           return
-        }
 
-      const nextRows = applyDuplicateUrlErrors (workingRows.map (row => {
-        const rowErrors = previewErrors.get (row.sourceRow)
-        if (rowErrors == null)
-          return row
-        return {
-            ...row,
-            validationErrors: rowErrors,
-            status: 'error' as const }
-      }))
-      await persistSession (buildSession (nextRows))
-      setLoading (false)
+        const nextRows = applyDuplicateUrlErrors (workingRows.map (row => {
+          const rowErrors = previewErrors.get (row.sourceRow)
+          if (rowErrors == null)
+            return row
+          return {
+              ...row,
+              validationErrors: rowErrors,
+              status: 'error' as const }
+        }))
+        await persistSession (buildSession (nextRows))
+      }
+      finally
+      {
+        if (active)
+	  setMetadataLoading (false)
+      }
     }
 
     const hydrate = async () => {
@@ -643,7 +649,7 @@ const PostImportReviewPage: FC<Props> = ({ user }) => {
       : rows
   const existingRows = sortedRows.filter (row => isExistingSkipRow (row))
   const reviewRows = sortedRows.filter (row => !(isExistingSkipRow (row)))
-  const busy = loading || loadingRow != null
+  const busy = metadataLoading || submitting || loadingRow != null
   const canSubmit =
       rows.every (row => isCompletedReviewRow (row))
       || processableImportRows (rows).length > 0
@@ -856,7 +862,7 @@ const PostImportReviewPage: FC<Props> = ({ user }) => {
 	return
       }
 
-    setLoading (true)
+    setSubmitting (true)
     try
     {
       const processingRows = processableImportRows (currentSession.rows)
@@ -887,7 +893,7 @@ const PostImportReviewPage: FC<Props> = ({ user }) => {
     }
     finally
     {
-      setLoading (false)
+      setSubmitting (false)
     }
   }
 
@@ -968,26 +974,29 @@ const PostImportReviewPage: FC<Props> = ({ user }) => {
 	</MainArea>
 
 	<PostImportFooter
-	    loading={busy}
+	    metadataLoading={metadataLoading}
+	    submitting={submitting}
 	    canSubmit={canSubmit}
 	    creatableCount={counts.creatable}
 	    manualSkippedCount={counts.manualSkipped}
 	    existingSkippedCount={counts.existingSkipped}
 	    pendingOrErrorCount={counts.pendingOrError}
-	    onBack={() => navigate (-1)}
+	    onBack={() => navigate ('/posts/new')}
 	    onSubmit={() => submit ()}/>
       </>)
 }
 
 const PostImportFooter = (
-    { loading,
+    { metadataLoading,
+      submitting,
       canSubmit,
       creatableCount,
       manualSkippedCount,
       existingSkippedCount,
       pendingOrErrorCount,
       onBack,
-      onSubmit }: { loading:              boolean
+      onSubmit }: { metadataLoading:      boolean
+		    submitting:           boolean
 		    canSubmit:            boolean
 		    creatableCount:       number
 		    manualSkippedCount:   number
@@ -1008,13 +1017,17 @@ const PostImportFooter = (
 	  <span>登録不可／未処理 {pendingOrErrorCount}件</span>
 	</div>
 	<div className="flex flex-col gap-2 sm:flex-row">
-	  <Button type="button" variant="outline" onClick={onBack} disabled={loading}>
+	  <Button
+	      type="button"
+	      variant="outline"
+	      onClick={onBack}
+	      disabled={submitting}>
 	    URL リスト入力へ戻る
 	  </Button>
 	  <Button
 	      type="button"
 	      onClick={onSubmit}
-	      disabled={loading || !(canSubmit)}>
+	      disabled={metadataLoading || submitting || !(canSubmit)}>
 	    {creatableCount > 1 ? '一括追加' : '追加'}
 	  </Button>
 	</div>