diff --git a/hgext/largefiles/overrides.py b/hgext/largefiles/overrides.py
--- a/hgext/largefiles/overrides.py
+++ b/hgext/largefiles/overrides.py
@@ -1853,7 +1853,7 @@ def upgraderequirements(orig, repo):
 
 
 @eh.wrapfunction(urlmod, b'open')
-def openlargefile(orig, ui, url_, data=None):
+def openlargefile(orig, ui, url_, data=None, **kwargs):
     if url_.startswith(_lfscheme):
         if data:
             msg = b"cannot use data on a 'largefile://' url"
@@ -1861,4 +1861,4 @@ def openlargefile(orig, ui, url_, data=N
         lfid = url_[len(_lfscheme) :]
         return storefactory.getlfile(ui, lfid)
     else:
-        return orig(ui, url_, data=data)
+        return orig(ui, url_, data=data, **kwargs)
diff --git a/tests/test-hgweb-diffs.t b/tests/test-hgweb-diffs.t
--- a/tests/test-hgweb-diffs.t
+++ b/tests/test-hgweb-diffs.t
@@ -1138,6 +1138,21 @@ test import rev as raw-rev
   $ cd test1
   $ hg import -q --bypass --exact http://localhost:$HGPORT/rev/1
 
+repeat test above, with largefiles enabled
+
+  $ cd ..
+  $ rm -r test1
+  $ hg clone -r0 test test1
+  adding changesets
+  adding manifests
+  adding file changes
+  added 1 changesets with 2 changes to 2 files
+  new changesets 0cd96de13884
+  updating to branch default
+  2 files updated, 0 files merged, 0 files removed, 0 files unresolved
+  $ cd test1
+  $ hg import --config extensions.largefiles= -q --bypass --exact http://localhost:$HGPORT/rev/1
+
 raw revision with diff block numbers
 
   $ killdaemons.py