diff --git a/cmk/gui/wato/_notification_parameter/_ms_teams.py b/cmk/gui/wato/_notification_parameter/_ms_teams.py
index a86c93abe27..76d33aeb1ef 100644
--- a/cmk/gui/wato/_notification_parameter/_ms_teams.py
+++ b/cmk/gui/wato/_notification_parameter/_ms_teams.py
@@ -4,6 +4,8 @@
 # conditions defined in the file COPYING, which is part of this source code package.
 
 
+from typing import cast
+
 from cmk.utils.ms_teams_constants import (
     ms_teams_tmpl_host_details,
     ms_teams_tmpl_host_summary,
@@ -13,21 +15,32 @@
     ms_teams_tmpl_svc_title,
 )
 
-from cmk.gui.i18n import _
-from cmk.gui.valuespec import (
-    CascadingDropdown,
+from cmk.gui.form_specs.private import SingleChoiceElementExtended, SingleChoiceExtended
+from cmk.gui.form_specs.vue.visitors.recomposers.unknown_form_spec import recompose
+from cmk.gui.valuespec import Dictionary as ValueSpecDictionary
+from cmk.gui.watolib.password_store import passwordstore_choices_without_user
+
+from cmk.rulesets.v1 import Help, Label, Message, Title
+from cmk.rulesets.v1.form_specs import (
+    CascadingSingleChoice,
+    CascadingSingleChoiceElement,
+    DefaultValue,
+    DictElement,
     Dictionary,
-    DropdownChoice,
+    FieldSize,
     FixedValue,
-    HTTPUrl,
-    TextAreaUnicode,
-    TextInput,
+    migrate_to_proxy,
+    MultilineText,
+    Proxy,
+    String,
 )
-from cmk.gui.wato import HTTPProxyReference
-from cmk.gui.watolib.password_store import passwordstore_choices
+from cmk.rulesets.v1.form_specs.validators import LengthInRange
 
 from ._base import NotificationParameter
-from ._helpers import get_url_prefix_specs, local_site_url, notification_macro_help
+from ._helpers import (
+    _get_url_prefix_setting,
+    notification_macro_help_fs,
+)
 
 
 class NotificationParameterMsTeams(NotificationParameter):
@@ -36,107 +49,107 @@ def ident(self) -> str:
         return "msteams"
 
     @property
-    def spec(self) -> Dictionary:
+    def spec(self) -> ValueSpecDictionary:
+        # TODO needed because of mixed Form Spec and old style setup
+        return cast(ValueSpecDictionary, recompose(self._form_spec()).valuespec)
+
+    def _form_spec(self):
         return Dictionary(
-            title=_("Create notification with the following parameters"),
-            elements=[
-                (
-                    "webhook_url",
-                    CascadingDropdown(
-                        title=_("Webhook URL"),
-                        help=_(
+            title=Title("Create notification with the following parameters"),
+            elements={
+                "webhook_url": DictElement(
+                    parameter_form=CascadingSingleChoice(
+                        title=Title("Webhook URL"),
+                        help_text=Help(
                             "Create a workflow 'Post to a channel when a "
                             "webhook request is received' for a channel in MS "
                             "Teams and use the generated webook URL.<br><br>"
                             "This URL can also be collected from the Password "
                             "Store from Checkmk."
                         ),
-                        choices=[
-                            (
-                                "webhook_url",
-                                _("Webhook URL"),
-                                HTTPUrl(size=80, allow_empty=False),
+                        elements=[
+                            CascadingSingleChoiceElement(
+                                name="webhook_url",
+                                title=Title("Webhook URL"),
+                                parameter_form=String(custom_validate=[LengthInRange(min_value=1)]),
                             ),
-                            (
-                                "store",
-                                _("URL from password store"),
-                                DropdownChoice(
-                                    sorted=True,
-                                    choices=passwordstore_choices,
+                            CascadingSingleChoiceElement(
+                                name="store",
+                                title=Title("URL from password store"),
+                                parameter_form=SingleChoiceExtended(
+                                    no_elements_text=Message(
+                                        "There are no elements defined for this selection yet."
+                                    ),
+                                    elements=[
+                                        SingleChoiceElementExtended(
+                                            title=Title("%s") % title, name=ident
+                                        )
+                                        for ident, title in passwordstore_choices_without_user()
+                                        if ident is not None
+                                    ],
+                                    type=str,
                                 ),
                             ),
                         ],
-                        sorted=False,
                     ),
                 ),
-                ("proxy_url", HTTPProxyReference()),
-                ("url_prefix", get_url_prefix_specs(local_site_url)),
-                (
-                    "host_title",
-                    TextInput(
-                        title=_("Title for host notifications"),
-                        help=notification_macro_help(),
-                        default_value=ms_teams_tmpl_host_title(),
-                        size=64,
+                "proxy_url": DictElement(parameter_form=Proxy(migrate=migrate_to_proxy)),
+                "url_prefix": _get_url_prefix_setting(),
+                "host_title": DictElement(
+                    parameter_form=String(
+                        title=Title("Title for host notifications"),
+                        help_text=notification_macro_help_fs(),
+                        prefill=DefaultValue(ms_teams_tmpl_host_title()),
+                        field_size=FieldSize.LARGE,
                     ),
                 ),
-                (
-                    "service_title",
-                    TextInput(
-                        title=_("Title for service notifications"),
-                        help=notification_macro_help(),
-                        default_value=ms_teams_tmpl_svc_title(),
-                        size=64,
+                "service_title": DictElement(
+                    parameter_form=String(
+                        title=Title("Title for service notifications"),
+                        help_text=notification_macro_help_fs(),
+                        prefill=DefaultValue(ms_teams_tmpl_svc_title()),
+                        field_size=FieldSize.LARGE,
                     ),
                 ),
-                (
-                    "host_summary",
-                    TextInput(
-                        title=_("Summary for host notifications"),
-                        help=notification_macro_help(),
-                        default_value=ms_teams_tmpl_host_summary(),
-                        size=64,
+                "host_summary": DictElement(
+                    parameter_form=String(
+                        title=Title("Summary for host notifications"),
+                        help_text=notification_macro_help_fs(),
+                        prefill=DefaultValue(ms_teams_tmpl_host_summary()),
+                        field_size=FieldSize.LARGE,
                     ),
                 ),
-                (
-                    "service_summary",
-                    TextInput(
-                        title=_("Summary for service notifications"),
-                        help=notification_macro_help(),
-                        default_value=ms_teams_tmpl_svc_summary(),
-                        size=64,
+                "service_summary": DictElement(
+                    parameter_form=String(
+                        title=Title("Summary for service notifications"),
+                        help_text=notification_macro_help_fs(),
+                        prefill=DefaultValue(ms_teams_tmpl_svc_summary()),
+                        field_size=FieldSize.LARGE,
                     ),
                 ),
-                (
-                    "host_details",
-                    TextAreaUnicode(
-                        title=_("Details for host notifications"),
-                        help=notification_macro_help(),
-                        rows=9,
-                        cols=58,
+                "host_details": DictElement(
+                    parameter_form=MultilineText(
+                        title=Title("Details for host notifications"),
+                        help_text=notification_macro_help_fs(),
                         monospaced=True,
-                        default_value=ms_teams_tmpl_host_details(),
+                        prefill=DefaultValue(ms_teams_tmpl_host_details()),
                     ),
                 ),
-                (
-                    "service_details",
-                    TextAreaUnicode(
-                        title=_("Details for service notifications"),
-                        help=notification_macro_help(),
-                        rows=11,
-                        cols=58,
+                "service_details": DictElement(
+                    parameter_form=MultilineText(
+                        title=Title("Details for service notifications"),
+                        help_text=notification_macro_help_fs(),
                         monospaced=True,
-                        default_value=ms_teams_tmpl_svc_details(),
+                        prefill=DefaultValue(ms_teams_tmpl_svc_details()),
                     ),
                 ),
-                (
-                    "affected_host_groups",
-                    FixedValue(
+                "affected_host_groups": DictElement(
+                    parameter_form=FixedValue(
                         value=True,
-                        title=_("Show affected host groups"),
-                        totext=_("Show affected host groups"),
-                        help=_("Show affected host groups in the created message."),
+                        title=Title("Show affected host groups"),
+                        label=Label("Show affected host groups"),
+                        help_text=Help("Show affected host groups in the created message."),
                     ),
                 ),
-            ],
+            },
         )