add open_in parameter

provider/app.go

@@ -2,6 +2,7 @@ package provider
 
 import (
 	"context"
+	"fmt"
 	"net/url"
 	"regexp"
 
@@ -83,6 +84,18 @@ func appResource() *schema.Resource {
 				Optional:      true,
 				ForceNew:      true,
 			},
+			"open_in": {
+				Type:        schema.TypeString,
+				Description: "The application to open the app in.",
+				Optional:    true,
+				ForceNew:    true,
+				ValidateFunc: func(i interface{}, s string) ([]string, []error) {
+					if s == "tab" || s == "window" || s == "slim-window" {
+						return nil, nil
+					}
+					return nil, []error{fmt.Errorf("invalid open_in value %q, must be one of \"tab\", \"window\" or \"slim-window\"", s)}
+				},
+			},
 			"icon": {
 				Type: schema.TypeString,
 				Description: "A URL to an icon that will display in the dashboard. View built-in " +