diff --git a/frankenphp.c b/frankenphp.c
index ea72e5ecca..6eaa9106af 100644
--- a/frankenphp.c
+++ b/frankenphp.c
@@ -141,7 +141,7 @@ typedef struct {
 } frankenphp_server_ctx;
 static THREAD_LOCAL frankenphp_server_ctx frankenphp_local_server_ctx;
 
-static inline uintptr_t frankenphp_thread_index(void) {
+uintptr_t frankenphp_thread_index(void) {
   frankenphp_server_ctx *ctx = (frankenphp_server_ctx *)SG(server_context);
   /* Fall back to the OS thread's own TLS before
    * frankenphp_update_request_context(). */
diff --git a/frankenphp.h b/frankenphp.h
index fe38b13c76..5eb6316947 100644
--- a/frankenphp.h
+++ b/frankenphp.h
@@ -221,4 +221,7 @@ typedef enum {
 
 void register_extensions(zend_module_entry **m, int len);
 
+// This function is exported for use by extensions, as proposed in PR #2305
+uintptr_t frankenphp_thread_index(void);
+
 #endif