diff --git a/docs/notifications.md b/docs/notifications.md
index 30a3dc20b9..02bafdd020 100644
--- a/docs/notifications.md
+++ b/docs/notifications.md
@@ -89,7 +89,7 @@ templating.
 | date             | string, time.Time          | Returns the text representation of the time in the specified format. For documentation on formats refer to [pkg.go.dev/time](https://pkg.go.dev/time#pkg-constants). |
 | dict             | values ...any              | Returns a map of string to any, constructed from the variadic list of key-value pairs. The number of arguments must be even, and the keys must be strings. |
 | humanizeDuration | number or string           | Returns a human-readable string representing the duration, and the error if it happened. |
-| join             | sep string, s []string     | [strings.Join](http://golang.org/pkg/strings/#Join), concatenates the elements of s to create a single string. The separator string sep is placed between elements in the resulting string. (note: argument order inverted for easier pipelining in templates.) |
+| join             | sep string, any            | [strings.Join](http://golang.org/pkg/strings/#Join), concatenates the elements of the provided slice to create a single string. The separator string sep is placed between elements in the resulting string. (note: argument order inverted for easier pipelining in templates.) |
 | list             | ...any                     | Returns the passed arguments as a slice of interfaces. |
 | match            | pattern, string            | [Regexp.MatchString](https://golang.org/pkg/regexp/#MatchString). Match a string using Regexp. |
 | now              |                            | [time.Now](https://pkg.go.dev/time#Now), returns the current local time. |
diff --git a/template/template.go b/template/template.go
index 73f1ac526f..d0a4ab34f1 100644
--- a/template/template.go
+++ b/template/template.go
@@ -185,8 +185,25 @@ var DefaultFuncs = FuncMap{
 	"trimSpace": strings.TrimSpace,
 	// join is equal to strings.Join but inverts the argument order
 	// for easier pipelining in templates.
-	"join": func(sep string, s []string) string {
-		return strings.Join(s, sep)
+	"join": func(sep string, v any) (string, error) {
+		if s, ok := v.([]string); ok {
+			return strings.Join(s, sep), nil
+		}
+
+		value := reflect.ValueOf(v)
+		switch {
+		case !value.IsValid():
+			return "", nil
+		case value.Kind() == reflect.Slice, value.Kind() == reflect.Array:
+			parts := make([]string, 0, value.Len())
+			for i := 0; i < value.Len(); i++ {
+				elem := value.Index(i).Interface()
+				parts = append(parts, fmt.Sprint(elem))
+			}
+			return strings.Join(parts, sep), nil
+		default:
+			return "", fmt.Errorf("join expects a slice or array, got %T", v)
+		}
 	},
 	"match": regexp.MatchString,
 	"safeHtml": func(text string) tmplhtml.HTML {
diff --git a/template/template_test.go b/template/template_test.go
index 3935f0bec0..f734d52db1 100644
--- a/template/template_test.go
+++ b/template/template_test.go
@@ -352,6 +352,16 @@ func TestTemplateExpansion(t *testing.T) {
 			data:  []string{"a", "b", "c"},
 			exp:   "a,b,c",
 		},
+		{
+			title: "Template using join with list",
+			in:    `{{ list "a" "b" "c" | join "," }}`,
+			exp:   "a,b,c",
+		},
+		{
+			title: "Template using join with mixed types",
+			in:    `{{ list 1 true "x" | join "," }}`,
+			exp:   "1,true,x",
+		},
 		{
 			title: "Text template without HTML escaping",
 			in:    `{{ "<b>" }}`,
@@ -621,6 +631,10 @@ func TestTemplateFuncs(t *testing.T) {
 		in:    `{{ . | join "," }}`,
 		data:  []string{"abc", "def"},
 		exp:   "abc,def",
+	}, {
+		title: "Template using join with list",
+		in:    `{{ list "abc" "def" | join "," }}`,
+		exp:   "abc,def",
 	}, {
 		title: "Template using match",
 		in:    `{{ match "[a-z]+" "abc" }}`,