diff --git a/aider/coders/base_coder.py b/aider/coders/base_coder.py
index 6f31bb817..7a3fd0990 100755
--- a/aider/coders/base_coder.py
+++ b/aider/coders/base_coder.py
@@ -553,9 +553,13 @@ class Coder:
 
         mentioned_fnames.update(self.get_ident_filename_matches(mentioned_idents))
 
-        other_files = set(self.get_all_abs_files()) - set(self.abs_fnames)
+        all_abs_files = set(self.get_all_abs_files())
+        repo_abs_read_only_fnames = set(self.abs_read_only_fnames) & all_abs_files
+        chat_files = set(self.abs_fnames) | repo_abs_read_only_fnames
+        other_files = all_abs_files - chat_files
+
         repo_content = self.repo_map.get_repo_map(
-            self.abs_fnames,
+            chat_files,
             other_files,
             mentioned_fnames=mentioned_fnames,
             mentioned_idents=mentioned_idents,
@@ -565,7 +569,7 @@ class Coder:
         if not repo_content:
             repo_content = self.repo_map.get_repo_map(
                 set(),
-                set(self.get_all_abs_files()),
+                all_abs_files,
                 mentioned_fnames=mentioned_fnames,
                 mentioned_idents=mentioned_idents,
             )
@@ -574,7 +578,7 @@ class Coder:
         if not repo_content:
             repo_content = self.repo_map.get_repo_map(
                 set(),
-                set(self.get_all_abs_files()),
+                all_abs_files,
             )
 
         return repo_content