diff --git a/src/plugins/guile/weechat-guile-api.c b/src/plugins/guile/weechat-guile-api.c
index 78423a12e..ba7863992 100644
--- a/src/plugins/guile/weechat-guile-api.c
+++ b/src/plugins/guile/weechat-guile-api.c
@@ -2003,6 +2003,30 @@ weechat_guile_api_config_unset_plugin (SCM option)
     API_RETURN_INT(rc);
 }
 
+SCM
+weechat_guile_api_theme_register (SCM name, SCM overrides)
+{
+    struct t_hashtable *c_overrides;
+    const char *result;
+    SCM return_value;
+
+    API_INIT_FUNC(1, "theme_register", API_RETURN_EMPTY);
+    if (!scm_is_string (name) || !scm_list_p (overrides))
+        API_WRONG_ARGS(API_RETURN_EMPTY);
+
+    c_overrides = weechat_guile_alist_to_hashtable (overrides,
+                                                    WEECHAT_SCRIPT_HASHTABLE_DEFAULT_SIZE,
+                                                    WEECHAT_HASHTABLE_STRING,
+                                                    WEECHAT_HASHTABLE_STRING);
+
+    result = API_PTR2STR(weechat_theme_register (API_SCM_TO_STRING(name),
+                                                 c_overrides));
+
+    weechat_hashtable_free (c_overrides);
+
+    API_RETURN_STRING(result);
+}
+
 SCM
 weechat_guile_api_key_bind (SCM context, SCM keys)
 {
@@ -5537,6 +5561,7 @@ weechat_guile_api_module_init (void *data)
     API_DEF_FUNC(config_set_plugin, 2);
     API_DEF_FUNC(config_set_desc_plugin, 2);
     API_DEF_FUNC(config_unset_plugin, 1);
+    API_DEF_FUNC(theme_register, 2);
     API_DEF_FUNC(key_bind, 2);
     API_DEF_FUNC(key_unbind, 2);
     API_DEF_FUNC(prefix, 1);
diff --git a/src/plugins/javascript/weechat-js-api.cpp b/src/plugins/javascript/weechat-js-api.cpp
index d2e045a48..5d69d2ac7 100644
--- a/src/plugins/javascript/weechat-js-api.cpp
+++ b/src/plugins/javascript/weechat-js-api.cpp
@@ -1898,6 +1898,28 @@ API_FUNC(config_unset_plugin)
     API_RETURN_INT(rc);
 }
 
+API_FUNC(theme_register)
+{
+    struct t_hashtable *hashtable;
+    const char *result;
+
+    API_INIT_FUNC(1, "theme_register", "sh", API_RETURN_EMPTY);
+
+    v8::String::Utf8Value name(args[0]);
+    hashtable = weechat_js_object_to_hashtable (
+        args[1]->ToObject(),
+        WEECHAT_SCRIPT_HASHTABLE_DEFAULT_SIZE,
+        WEECHAT_HASHTABLE_STRING,
+        WEECHAT_HASHTABLE_STRING);
+
+    result = API_PTR2STR(weechat_theme_register (*name, hashtable));
+
+    if (hashtable)
+        weechat_hashtable_free (hashtable);
+
+    API_RETURN_STRING(result);
+}
+
 API_FUNC(key_bind)
 {
     struct t_hashtable *hashtable;
@@ -5468,6 +5490,7 @@ WeechatJsV8::loadLibs()
     API_DEF_FUNC(config_set_plugin);
     API_DEF_FUNC(config_set_desc_plugin);
     API_DEF_FUNC(config_unset_plugin);
+    API_DEF_FUNC(theme_register);
     API_DEF_FUNC(key_bind);
     API_DEF_FUNC(key_unbind);
     API_DEF_FUNC(prefix);
diff --git a/src/plugins/lua/weechat-lua-api.c b/src/plugins/lua/weechat-lua-api.c
index e7822995a..3ae79952b 100644
--- a/src/plugins/lua/weechat-lua-api.c
+++ b/src/plugins/lua/weechat-lua-api.c
@@ -2081,6 +2081,29 @@ API_FUNC(config_unset_plugin)
     API_RETURN_INT(rc);
 }
 
+API_FUNC(theme_register)
+{
+    const char *name;
+    struct t_hashtable *hashtable;
+    const char *result;
+
+    API_INIT_FUNC(1, "theme_register", API_RETURN_EMPTY);
+    if (lua_gettop (L) < 2)
+        API_WRONG_ARGS(API_RETURN_EMPTY);
+
+    name = lua_tostring (L, -2);
+    hashtable = weechat_lua_tohashtable (L, -1,
+                                         WEECHAT_SCRIPT_HASHTABLE_DEFAULT_SIZE,
+                                         WEECHAT_HASHTABLE_STRING,
+                                         WEECHAT_HASHTABLE_STRING);
+
+    result = API_PTR2STR(weechat_theme_register (name, hashtable));
+
+    weechat_hashtable_free (hashtable);
+
+    API_RETURN_STRING(result);
+}
+
 API_FUNC(key_bind)
 {
     const char *context;
@@ -5849,6 +5872,7 @@ const struct luaL_Reg weechat_lua_api_funcs[] = {
     API_DEF_FUNC(config_set_plugin),
     API_DEF_FUNC(config_set_desc_plugin),
     API_DEF_FUNC(config_unset_plugin),
+    API_DEF_FUNC(theme_register),
     API_DEF_FUNC(key_bind),
     API_DEF_FUNC(key_unbind),
     API_DEF_FUNC(prefix),
diff --git a/src/plugins/perl/weechat-perl-api.c b/src/plugins/perl/weechat-perl-api.c
index 7c3b400df..9c19676a7 100644
--- a/src/plugins/perl/weechat-perl-api.c
+++ b/src/plugins/perl/weechat-perl-api.c
@@ -2000,6 +2000,30 @@ API_FUNC(config_unset_plugin)
     API_RETURN_INT(rc);
 }
 
+API_FUNC(theme_register)
+{
+    char *name;
+    struct t_hashtable *hashtable;
+    const char *result;
+    dXSARGS;
+
+    API_INIT_FUNC(1, "theme_register", API_RETURN_EMPTY);
+    if (items < 2)
+        API_WRONG_ARGS(API_RETURN_EMPTY);
+
+    name = SvPV_nolen (ST (0));
+    hashtable = weechat_perl_hash_to_hashtable (ST (1),
+                                                WEECHAT_SCRIPT_HASHTABLE_DEFAULT_SIZE,
+                                                WEECHAT_HASHTABLE_STRING,
+                                                WEECHAT_HASHTABLE_STRING);
+
+    result = API_PTR2STR(weechat_theme_register (name, hashtable));
+
+    weechat_hashtable_free (hashtable);
+
+    API_RETURN_STRING(result);
+}
+
 API_FUNC(key_bind)
 {
     char *context;
@@ -5801,6 +5825,7 @@ weechat_perl_api_init (pTHX)
     API_DEF_FUNC(config_set_plugin);
     API_DEF_FUNC(config_set_desc_plugin);
     API_DEF_FUNC(config_unset_plugin);
+    API_DEF_FUNC(theme_register);
     API_DEF_FUNC(key_bind);
     API_DEF_FUNC(key_unbind);
     API_DEF_FUNC(prefix);
diff --git a/src/plugins/php/weechat-php-api.c b/src/plugins/php/weechat-php-api.c
index 8238eaa67..c461c077a 100644
--- a/src/plugins/php/weechat-php-api.c
+++ b/src/plugins/php/weechat-php-api.c
@@ -2175,6 +2175,33 @@ API_FUNC(config_unset_plugin)
     API_RETURN_INT(result);
 }
 
+API_FUNC(theme_register)
+{
+    zend_string *z_name;
+    zval *z_overrides;
+    char *name;
+    struct t_hashtable *overrides;
+    const char *result;
+
+    API_INIT_FUNC(1, "theme_register", API_RETURN_EMPTY);
+    if (zend_parse_parameters (ZEND_NUM_ARGS(), "Sa", &z_name,
+                               &z_overrides) == FAILURE)
+        API_WRONG_ARGS(API_RETURN_EMPTY);
+
+    name = ZSTR_VAL(z_name);
+    overrides = weechat_php_array_to_hashtable (z_overrides,
+                                                WEECHAT_SCRIPT_HASHTABLE_DEFAULT_SIZE,
+                                                WEECHAT_HASHTABLE_STRING,
+                                                WEECHAT_HASHTABLE_STRING);
+
+    result = API_PTR2STR(weechat_theme_register ((const char *)name,
+                                                 overrides));
+
+    weechat_hashtable_free (overrides);
+
+    API_RETURN_STRING(result);
+}
+
 API_FUNC(key_bind)
 {
     zend_string *z_context;
diff --git a/src/plugins/php/weechat-php-api.h b/src/plugins/php/weechat-php-api.h
index b878a4ef5..4096a6d80 100644
--- a/src/plugins/php/weechat-php-api.h
+++ b/src/plugins/php/weechat-php-api.h
@@ -132,6 +132,7 @@ PHP_FUNCTION(weechat_config_is_set_plugin);
 PHP_FUNCTION(weechat_config_set_plugin);
 PHP_FUNCTION(weechat_config_set_desc_plugin);
 PHP_FUNCTION(weechat_config_unset_plugin);
+PHP_FUNCTION(weechat_theme_register);
 PHP_FUNCTION(weechat_key_bind);
 PHP_FUNCTION(weechat_key_unbind);
 PHP_FUNCTION(weechat_prefix);
diff --git a/src/plugins/php/weechat-php.c b/src/plugins/php/weechat-php.c
index c20ec9d3e..05a0c3ef6 100644
--- a/src/plugins/php/weechat-php.c
+++ b/src/plugins/php/weechat-php.c
@@ -190,6 +190,7 @@ const zend_function_entry weechat_functions[] = {
     PHP_FE(weechat_config_set_plugin, arginfo_weechat_config_set_plugin)
     PHP_FE(weechat_config_set_desc_plugin, arginfo_weechat_config_set_desc_plugin)
     PHP_FE(weechat_config_unset_plugin, arginfo_weechat_config_unset_plugin)
+    PHP_FE(weechat_theme_register, arginfo_weechat_theme_register)
     PHP_FE(weechat_key_bind, arginfo_weechat_key_bind)
     PHP_FE(weechat_key_unbind, arginfo_weechat_key_unbind)
     PHP_FE(weechat_prefix, arginfo_weechat_prefix)
diff --git a/src/plugins/php/weechat-php_arginfo.h b/src/plugins/php/weechat-php_arginfo.h
index 2345bc686..0e74af377 100644
--- a/src/plugins/php/weechat-php_arginfo.h
+++ b/src/plugins/php/weechat-php_arginfo.h
@@ -233,6 +233,11 @@ ZEND_END_ARG_INFO()
 
 #define arginfo_weechat_config_unset_plugin arginfo_weechat_charset_set
 
+ZEND_BEGIN_ARG_WITH_RETURN_TYPE_INFO_EX(arginfo_weechat_theme_register, 0, 2, IS_STRING, 0)
+	ZEND_ARG_TYPE_INFO(0, p0, IS_STRING, 0)
+	ZEND_ARG_TYPE_INFO(0, p1, IS_ARRAY, 0)
+ZEND_END_ARG_INFO()
+
 ZEND_BEGIN_ARG_WITH_RETURN_TYPE_INFO_EX(arginfo_weechat_key_bind, 0, 2, IS_LONG, 0)
 	ZEND_ARG_TYPE_INFO(0, p0, IS_STRING, 0)
 	ZEND_ARG_TYPE_INFO(0, p1, IS_ARRAY, 0)
diff --git a/src/plugins/php/weechat-php_legacy_arginfo.h b/src/plugins/php/weechat-php_legacy_arginfo.h
index e8de9d8ac..a8b3b8db5 100644
--- a/src/plugins/php/weechat-php_legacy_arginfo.h
+++ b/src/plugins/php/weechat-php_legacy_arginfo.h
@@ -194,6 +194,8 @@ ZEND_END_ARG_INFO()
 
 #define arginfo_weechat_config_unset_plugin arginfo_weechat_plugin_get_name
 
+#define arginfo_weechat_theme_register arginfo_weechat_iconv_to_internal
+
 #define arginfo_weechat_key_bind arginfo_weechat_iconv_to_internal
 
 #define arginfo_weechat_key_unbind arginfo_weechat_iconv_to_internal
diff --git a/src/plugins/python/weechat-python-api.c b/src/plugins/python/weechat-python-api.c
index 88194ba71..6745a3511 100644
--- a/src/plugins/python/weechat-python-api.c
+++ b/src/plugins/python/weechat-python-api.c
@@ -2001,6 +2001,31 @@ API_FUNC(config_unset_plugin)
     API_RETURN_INT(rc);
 }
 
+API_FUNC(theme_register)
+{
+    char *name;
+    PyObject *dict;
+    struct t_hashtable *hashtable;
+    const char *result;
+
+    API_INIT_FUNC(1, "theme_register", API_RETURN_EMPTY);
+    name = NULL;
+    dict = NULL;
+    if (!PyArg_ParseTuple (args, "sO", &name, &dict))
+        API_WRONG_ARGS(API_RETURN_EMPTY);
+
+    hashtable = weechat_python_dict_to_hashtable (dict,
+                                                  WEECHAT_SCRIPT_HASHTABLE_DEFAULT_SIZE,
+                                                  WEECHAT_HASHTABLE_STRING,
+                                                  WEECHAT_HASHTABLE_STRING);
+
+    result = API_PTR2STR(weechat_theme_register (name, hashtable));
+
+    weechat_hashtable_free (hashtable);
+
+    API_RETURN_STRING(result);
+}
+
 API_FUNC(key_bind)
 {
     char *context;
@@ -5729,6 +5754,7 @@ PyMethodDef weechat_python_funcs[] =
     API_DEF_FUNC(config_set_plugin),
     API_DEF_FUNC(config_set_desc_plugin),
     API_DEF_FUNC(config_unset_plugin),
+    API_DEF_FUNC(theme_register),
     API_DEF_FUNC(key_bind),
     API_DEF_FUNC(key_unbind),
     API_DEF_FUNC(prefix),
diff --git a/src/plugins/python/weechat.pyi b/src/plugins/python/weechat.pyi
index a9f5abb82..d953ec7a5 100644
--- a/src/plugins/python/weechat.pyi
+++ b/src/plugins/python/weechat.pyi
@@ -1143,6 +1143,19 @@ def config_unset_plugin(option_name: str) -> int:
     ...
 
 
+def theme_register(name: str, overrides: Dict[str, str]) -> str:
+    """`theme_register in WeeChat plugin API reference <https://weechat.org/doc/weechat/api/#_theme_register>`_
+    ::
+
+        # example
+        weechat.theme_register("light", {
+            "irc.color.input_nick": "cyan",
+            "irc.color.topic_old": "darkgray",
+        })
+    """
+    ...
+
+
 def key_bind(context: str, keys: Dict[str, str]) -> int:
     """`key_bind in WeeChat plugin API reference <https://weechat.org/doc/weechat/api/#_key_bind>`_
     ::
diff --git a/src/plugins/ruby/weechat-ruby-api.c b/src/plugins/ruby/weechat-ruby-api.c
index a5acd17cb..b7ba1805d 100644
--- a/src/plugins/ruby/weechat-ruby-api.c
+++ b/src/plugins/ruby/weechat-ruby-api.c
@@ -2478,6 +2478,33 @@ weechat_ruby_api_config_unset_plugin (VALUE class, VALUE option)
     API_RETURN_INT(rc);
 }
 
+static VALUE
+weechat_ruby_api_theme_register (VALUE class, VALUE name, VALUE overrides)
+{
+    char *c_name;
+    struct t_hashtable *c_overrides;
+    const char *result;
+
+    API_INIT_FUNC(1, "theme_register", API_RETURN_EMPTY);
+    if (NIL_P (name) || NIL_P (overrides))
+        API_WRONG_ARGS(API_RETURN_EMPTY);
+
+    Check_Type (name, T_STRING);
+    Check_Type (overrides, T_HASH);
+
+    c_name = StringValuePtr (name);
+    c_overrides = weechat_ruby_hash_to_hashtable (overrides,
+                                                  WEECHAT_SCRIPT_HASHTABLE_DEFAULT_SIZE,
+                                                  WEECHAT_HASHTABLE_STRING,
+                                                  WEECHAT_HASHTABLE_STRING);
+
+    result = API_PTR2STR(weechat_theme_register (c_name, c_overrides));
+
+    weechat_hashtable_free (c_overrides);
+
+    API_RETURN_STRING(result);
+}
+
 static VALUE
 weechat_ruby_api_key_bind (VALUE class, VALUE context, VALUE keys)
 {
@@ -7078,6 +7105,7 @@ weechat_ruby_api_init (VALUE ruby_mWeechat)
     API_DEF_FUNC(config_set_plugin, 2);
     API_DEF_FUNC(config_set_desc_plugin, 2);
     API_DEF_FUNC(config_unset_plugin, 1);
+    API_DEF_FUNC(theme_register, 2);
     API_DEF_FUNC(key_bind, 2);
     API_DEF_FUNC(key_unbind, 2);
     API_DEF_FUNC(prefix, 1);
diff --git a/src/plugins/tcl/weechat-tcl-api.c b/src/plugins/tcl/weechat-tcl-api.c
index 2fff10faf..816126274 100644
--- a/src/plugins/tcl/weechat-tcl-api.c
+++ b/src/plugins/tcl/weechat-tcl-api.c
@@ -2035,6 +2035,29 @@ API_FUNC(config_unset_plugin)
     API_RETURN_INT(rc);
 }
 
+API_FUNC(theme_register)
+{
+    char *name;
+    struct t_hashtable *hashtable;
+    const char *result;
+
+    API_INIT_FUNC(1, "theme_register", API_RETURN_EMPTY);
+    if (objc < 3)
+        API_WRONG_ARGS(API_RETURN_EMPTY);
+
+    name = Tcl_GetString (objv[1]);
+    hashtable = weechat_tcl_dict_to_hashtable (interp, objv[2],
+                                               WEECHAT_SCRIPT_HASHTABLE_DEFAULT_SIZE,
+                                               WEECHAT_HASHTABLE_STRING,
+                                               WEECHAT_HASHTABLE_STRING);
+
+    result = API_PTR2STR(weechat_theme_register (name, hashtable));
+
+    weechat_hashtable_free (hashtable);
+
+    API_RETURN_STRING(result);
+}
+
 API_FUNC(key_bind)
 {
     char *context;
@@ -5806,6 +5829,7 @@ void weechat_tcl_api_init (Tcl_Interp *interp)
     API_DEF_FUNC(config_set_plugin);
     API_DEF_FUNC(config_set_desc_plugin);
     API_DEF_FUNC(config_unset_plugin);
+    API_DEF_FUNC(theme_register);
     API_DEF_FUNC(key_bind);
     API_DEF_FUNC(key_unbind);
     API_DEF_FUNC(prefix);