diff --git a/docs/source/conf.py b/docs/source/conf.py
index 607e088da..d97fb99a7 100644
--- a/docs/source/conf.py
+++ b/docs/source/conf.py
@@ -16,15 +16,17 @@ html_theme_options: dict[str] = {
     "source_branch": "main",
     "source_directory": "docs/source/",
 }
+html_context: dict[str] = {}
 
 # try to fix the readthedocs detection
-html_context: dict[str] = {
-    "READTHEDOCS": True,
-    "display_github": True,
-    "github_user": "YosysHQ",
-    "github_repo": "yosys",
-    "slug": "yosys",
-}
+if os.getenv("READTHEDOCS"):
+    html_context.update({
+        "READTHEDOCS": True,
+        "display_github": True,
+        "github_user": "YosysHQ",
+        "github_repo": "yosys",
+        "slug": "yosys",
+    })
 
 # override source_branch if not main
 git_slug = os.getenv("READTHEDOCS_VERSION_NAME")