diff --git a/src/html/generator.ml b/src/html/generator.ml
index 91cbd3884c..319bbf2757 100644
--- a/src/html/generator.ml
+++ b/src/html/generator.ml
@@ -368,24 +368,27 @@ module Page = struct
         | `Closed | `Open | `Default -> None
         | `Inline -> Some 0 )
 
-  let rec include_ ?theme_uri { Subpage.content; _ } =
-    [ page ?theme_uri content ]
+  let rec include_ ?theme_uri indent { Subpage.content; _ } =
+    [ page ?theme_uri indent content ]
 
-  and subpages ?theme_uri i =
-    Utils.list_concat_map ~f:(include_ ?theme_uri) @@ Doctree.Subpages.compute i
+  and subpages ?theme_uri indent i =
+    Utils.list_concat_map ~f:(include_ ?theme_uri indent)
+    @@ Doctree.Subpages.compute i
 
-  and page ?theme_uri ({ Page.title; header; items = i; url } as p) =
+  and page ?theme_uri indent ({ Page.title; header; items = i; url } as p) =
     let resolve = Link.Current url in
     let i = Doctree.Shift.compute ~on_sub i in
     let toc = Toc.from_items ~resolve ~path:url i in
-    let subpages = subpages ?theme_uri p in
+    let subpages = subpages ?theme_uri indent p in
     let header = items ~resolve header in
     let content = (items ~resolve i :> any Html.elt list) in
-    let page = Tree.make ?theme_uri ~header ~toc ~url title content subpages in
+    let page =
+      Tree.make ?theme_uri ~indent ~header ~toc ~url title content subpages
+    in
     page
 end
 
-let render ?theme_uri page = Page.page ?theme_uri page
+let render ?theme_uri ~indent page = Page.page ?theme_uri indent page
 
 let doc ~xref_base_uri b =
   let resolve = Link.Base xref_base_uri in
diff --git a/src/html/generator.mli b/src/html/generator.mli
index d579a29d53..121388401c 100644
--- a/src/html/generator.mli
+++ b/src/html/generator.mli
@@ -1,6 +1,6 @@
 open Odoc_document
 
-val render : ?theme_uri:Tree.uri -> Types.Page.t -> Renderer.page
+val render : ?theme_uri:Tree.uri -> indent:bool -> Types.Page.t -> Renderer.page
 
 val doc :
   xref_base_uri:string ->
diff --git a/src/html/tree.ml b/src/html/tree.ml
index fe1bd1d546..3afb4997e7 100644
--- a/src/html/tree.ml
+++ b/src/html/tree.ml
@@ -114,10 +114,10 @@ let page_creator ?(theme_uri = Relative "./") ~url name header toc content =
   in
   Html.html head (Html.body body)
 
-let make ?theme_uri ~url ~header ~toc title content children =
+let make ?theme_uri ~indent ~url ~header ~toc title content children =
   let filename = Link.Path.as_filename url in
   let html = page_creator ?theme_uri ~url title header toc content in
-  let content ppf = (Html.pp ()) ppf html in
+  let content ppf = (Html.pp ~indent ()) ppf html in
   { Odoc_document.Renderer.filename; content; children }
 
 let open_details = ref true
diff --git a/src/html/tree.mli b/src/html/tree.mli
index d927d51d21..b48010c0d5 100644
--- a/src/html/tree.mli
+++ b/src/html/tree.mli
@@ -29,6 +29,7 @@ type uri =
 
 val make :
   ?theme_uri:uri ->
+  indent:bool ->
   url:Url.Path.t ->
   header:Html_types.flow5_without_header_footer Html.elt list ->
   toc:Html_types.flow5 Html.elt list ->
diff --git a/src/odoc/bin/main.ml b/src/odoc/bin/main.ml
index 6552e611aa..ca094c773e 100644
--- a/src/odoc/bin/main.ml
+++ b/src/odoc/bin/main.ml
@@ -377,6 +377,10 @@ module Odoc_html = Make_renderer (struct
     in
     Arg.(value & flag (info ~doc [ "closed-details" ]))
 
+  let indent =
+    let doc = "Format the output HTML files with indentation" in
+    Arg.(value & flag (info ~doc [ "indent" ]))
+
   (* Very basic validation and normalization for URI paths. *)
   let convert_uri : Odoc_html.Tree.uri Arg.converter =
     let parser str =
@@ -409,10 +413,10 @@ module Odoc_html = Make_renderer (struct
       value & opt convert_uri default & info ~docv:"URI" ~doc [ "theme-uri" ])
 
   let extra_args =
-    let f semantic_uris closed_details theme_uri =
-      { Html_page.semantic_uris; closed_details; theme_uri }
+    let f semantic_uris closed_details indent theme_uri =
+      { Html_page.semantic_uris; closed_details; theme_uri; indent }
     in
-    Term.(const f $ semantic_uris $ closed_details $ theme_uri)
+    Term.(const f $ semantic_uris $ closed_details $ indent $ theme_uri)
 end)
 
 module Html_fragment : sig
diff --git a/src/odoc/html_page.ml b/src/odoc/html_page.ml
index 12e0e1717c..fb5c011268 100644
--- a/src/odoc/html_page.ml
+++ b/src/odoc/html_page.ml
@@ -19,13 +19,14 @@ open Odoc_document
 type args = {
   semantic_uris : bool;
   closed_details : bool;
+  indent : bool;
   theme_uri : Odoc_html.Tree.uri;
 }
 
 let render args page =
   Odoc_html.Link.semantic_uris := args.semantic_uris;
   Odoc_html.Tree.open_details := not args.closed_details;
-  Odoc_html.Generator.render ~theme_uri:args.theme_uri page
+  Odoc_html.Generator.render ~theme_uri:args.theme_uri ~indent:args.indent page
 
 let files_of_url url = [ Odoc_html.Link.Path.as_filename url ]
 
diff --git a/src/odoc/html_page.mli b/src/odoc/html_page.mli
index 432ccaefb9..e3471a6404 100644
--- a/src/odoc/html_page.mli
+++ b/src/odoc/html_page.mli
@@ -19,6 +19,7 @@ open Odoc_document
 type args = {
   semantic_uris : bool;
   closed_details : bool;
+  indent : bool;
   theme_uri : Odoc_html.Tree.uri;
 }
 
diff --git a/src/xref2/compile.ml b/src/xref2/compile.ml
index 53d0da042f..914fa28e12 100644
--- a/src/xref2/compile.ml
+++ b/src/xref2/compile.ml
@@ -64,7 +64,7 @@ and content env id =
   | Module m ->
       let sg = Type_of.signature env m in
       Module (signature env (id :> Id.Signature.t) sg)
-  | Pack _ -> failwith "Unhandled content"
+  | Pack p -> Pack p
 
 and value_ env parent t =
   let open Value in
diff --git a/src/xref2/env.ml b/src/xref2/env.ml
index 4c4afee520..b0a8cb1792 100644
--- a/src/xref2/env.ml
+++ b/src/xref2/env.ml
@@ -346,7 +346,19 @@ let module_of_unit : Odoc_model.Lang.Compilation_unit.t -> Component.Module.t =
       in
       let ty = Component.Of_Lang.(module_ empty m) in
       ty
-  | Pack _ -> failwith "Unsupported"
+  | Pack _p ->
+      let m =
+        Odoc_model.Lang.Module.
+          {
+            id = (unit.id :> Odoc_model.Paths.Identifier.Module.t);
+            doc = unit.doc;
+            type_ = ModuleType (Signature []);
+            canonical = None;
+            hidden = unit.hidden;
+          }
+      in
+      let ty = Component.Of_Lang.(module_ empty m) in
+      ty
 
 let lookup_root_module name env =
   let result =
diff --git a/src/xref2/link.ml b/src/xref2/link.ml
index 45d4906139..a602d7899c 100644
--- a/src/xref2/link.ml
+++ b/src/xref2/link.ml
@@ -118,7 +118,7 @@ and content env id =
   let open Compilation_unit in
   function
   | Module m -> Module (signature env (id :> Id.Signature.t) m)
-  | Pack _ -> failwith "Unhandled content"
+  | Pack p -> Pack p
 
 and value_ env parent t =
   let open Value in