diff --git a/generated/google-apis-chat_v1/CHANGELOG.md b/generated/google-apis-chat_v1/CHANGELOG.md
index 3ce5f28672e..bbe563b5802 100644
--- a/generated/google-apis-chat_v1/CHANGELOG.md
+++ b/generated/google-apis-chat_v1/CHANGELOG.md
@@ -1,5 +1,9 @@
 # Release history for google-apis-chat_v1
 
+### v0.140.0 (2025-12-14)
+
+* Regenerated from discovery document revision 20251207
+
 ### v0.139.0 (2025-11-23)
 
 * Regenerated from discovery document revision 20251118
diff --git a/generated/google-apis-chat_v1/lib/google/apis/chat_v1/classes.rb b/generated/google-apis-chat_v1/lib/google/apis/chat_v1/classes.rb
index edd2da98be6..b4875922846 100644
--- a/generated/google-apis-chat_v1/lib/google/apis/chat_v1/classes.rb
+++ b/generated/google-apis-chat_v1/lib/google/apis/chat_v1/classes.rb
@@ -1867,9 +1867,7 @@ class GoogleAppsCardV1Card
         attr_accessor :display_style
       
         # The expression data for the card. Available for Google Workspace add-ons that
-        # extend Google Workspace flows, which is available as part of the [Gemini Alpha
-        # program](https://support.google.com/a/answer/14170809). Unavailable for Google
-        # Chat apps.
+        # extend Google Workspace Studio. Unavailable for Google Chat apps.
         # Corresponds to the JSON property `expressionData`
         # @return [Array<Google::Apis::ChatV1::GoogleAppsCardV1ExpressionData>]
         attr_accessor :expression_data
@@ -2331,16 +2329,14 @@ def update!(**args)
       end
       
       # Represents an action that is not specific to a widget. Available for Google
-      # Workspace add-ons that extend Google Workspace flows, which is available as
-      # part of the [Gemini Alpha program](https://support.google.com/a/answer/
-      # 14170809). Unavailable for Google Chat apps.
+      # Workspace add-ons that extend Google Workspace Studio. Unavailable for Google
+      # Chat apps.
       class GoogleAppsCardV1CommonWidgetAction
         include Google::Apis::Core::Hashable
       
         # Represents an action that updates the visibility of a widget. Available for
-        # Google Workspace add-ons that extend Google Workspace flows, which is
-        # available as part of the [Gemini Alpha program](https://support.google.com/a/
-        # answer/14170809). Unavailable for Google Chat apps.
+        # Google Workspace add-ons that extend Google Workspace Studio. Unavailable for
+        # Google Chat apps.
         # Corresponds to the JSON property `updateVisibilityAction`
         # @return [Google::Apis::ChatV1::GoogleAppsCardV1UpdateVisibilityAction]
         attr_accessor :update_visibility_action
@@ -2356,9 +2352,8 @@ def update!(**args)
       end
       
       # Represents a condition that can be used to trigger an action. Available for
-      # Google Workspace add-ons that extend Google Workspace flows, which is
-      # available as part of the [Gemini Alpha program](https://support.google.com/a/
-      # answer/14170809). Unavailable for Google Chat apps.
+      # Google Workspace add-ons that extend Google Workspace Studio. Unavailable for
+      # Google Chat apps.
       class GoogleAppsCardV1Condition
         include Google::Apis::Core::Hashable
       
@@ -2368,9 +2363,8 @@ class GoogleAppsCardV1Condition
         attr_accessor :action_rule_id
       
         # Represents a condition that is evaluated using CEL. Available for Google
-        # Workspace add-ons that extend Google Workspace flows, which is available as
-        # part of the [Gemini Alpha program](https://support.google.com/a/answer/
-        # 14170809). Unavailable for Google Chat apps.
+        # Workspace add-ons that extend Google Workspace Studio. Unavailable for Google
+        # Chat apps.
         # Corresponds to the JSON property `expressionDataCondition`
         # @return [Google::Apis::ChatV1::GoogleAppsCardV1ExpressionDataCondition]
         attr_accessor :expression_data_condition
@@ -2387,9 +2381,8 @@ def update!(**args)
       end
       
       # A configuration object that helps configure the data sources for a widget.
-      # Available for Google Workspace add-ons that extend Google Workspace flows,
-      # which is available as part of the [Gemini Alpha program](https://support.
-      # google.com/a/answer/14170809). Unavailable for Google Chat apps.
+      # Available for Google Workspace add-ons that extend Google Workspace Studio.
+      # Unavailable for Google Chat apps.
       class GoogleAppsCardV1DataSourceConfig
         include Google::Apis::Core::Hashable
       
@@ -2681,9 +2674,8 @@ def update!(**args)
       end
       
       # Represents an actionthat can be performed on an ui element. Available for
-      # Google Workspace add-ons that extend Google Workspace flows, which is
-      # available as part of the [Gemini Alpha program](https://support.google.com/a/
-      # answer/14170809). Unavailable for Google Chat apps.
+      # Google Workspace add-ons that extend Google Workspace Studio. Unavailable for
+      # Google Chat apps.
       class GoogleAppsCardV1EventAction
         include Google::Apis::Core::Hashable
       
@@ -2693,9 +2685,8 @@ class GoogleAppsCardV1EventAction
         attr_accessor :action_rule_id
       
         # Represents an action that is not specific to a widget. Available for Google
-        # Workspace add-ons that extend Google Workspace flows, which is available as
-        # part of the [Gemini Alpha program](https://support.google.com/a/answer/
-        # 14170809). Unavailable for Google Chat apps.
+        # Workspace add-ons that extend Google Workspace Studio. Unavailable for Google
+        # Chat apps.
         # Corresponds to the JSON property `commonWidgetAction`
         # @return [Google::Apis::ChatV1::GoogleAppsCardV1CommonWidgetAction]
         attr_accessor :common_widget_action
@@ -2718,9 +2709,8 @@ def update!(**args)
       end
       
       # Represents the data that is used to evaluate an expression. Available for
-      # Google Workspace add-ons that extend Google Workspace flows, which is
-      # available as part of the [Gemini Alpha program](https://support.google.com/a/
-      # answer/14170809). Unavailable for Google Chat apps.
+      # Google Workspace add-ons that extend Google Workspace Studio. Unavailable for
+      # Google Chat apps.
       class GoogleAppsCardV1ExpressionData
         include Google::Apis::Core::Hashable
       
@@ -2758,9 +2748,8 @@ def update!(**args)
       end
       
       # Represents a condition that is evaluated using CEL. Available for Google
-      # Workspace add-ons that extend Google Workspace flows, which is available as
-      # part of the [Gemini Alpha program](https://support.google.com/a/answer/
-      # 14170809). Unavailable for Google Chat apps.
+      # Workspace add-ons that extend Google Workspace Studio. Unavailable for Google
+      # Chat apps.
       class GoogleAppsCardV1ExpressionDataCondition
         include Google::Apis::Core::Hashable
       
@@ -3269,7 +3258,7 @@ class GoogleAppsCardV1OpenLink
         # @return [String]
         attr_accessor :open_as
       
-        # The URL to open.
+        # The URL to open. HTTP URLs are converted to HTTPS.
         # Corresponds to the JSON property `url`
         # @return [String]
         attr_accessor :url
@@ -3420,9 +3409,7 @@ class GoogleAppsCardV1Section
         # A unique ID assigned to the section that's used to identify the section to be
         # mutated. The ID has a character limit of 64 characters and should be in the
         # format of `[a-zA-Z0-9-]+`. Available for Google Workspace add-ons that extend
-        # Google Workspace flows, which is available as part of the [Gemini Alpha
-        # program](https://support.google.com/a/answer/14170809). Unavailable for Google
-        # Chat apps.
+        # Google Workspace Studio. Unavailable for Google Chat apps.
         # Corresponds to the JSON property `id`
         # @return [String]
         attr_accessor :id
@@ -3477,9 +3464,11 @@ class GoogleAppsCardV1SelectionInput
         # provides more fine-grained control over the data source. If specified, the `
         # multi_select_max_selected_items` field, `multi_select_min_query_length` field,
         # `external_data_source` field and `platform_data_source` field are ignored.
-        # Available for Google Workspace add-ons that extend Google Workspace flows,
-        # which is available as part of the [Gemini Alpha program](https://support.
-        # google.com/a/answer/14170809). Unavailable for Google Chat apps.
+        # Available for Google Workspace add-ons that extend Google Workspace Studio.
+        # Available for the `Dropdown widget` widget in Google Chat apps as part of the [
+        # Developer Preview Program](https://developers.google.com/workspace/preview).
+        # For the `Dropdown` widget in Google Chat apps, only one `DataSourceConfig` is
+        # supported. If multiple `DataSourceConfig`s are set, only the first one is used.
         # Corresponds to the JSON property `dataSourceConfigs`
         # @return [Array<Google::Apis::ChatV1::GoogleAppsCardV1DataSourceConfig>]
         attr_accessor :data_source_configs
@@ -3494,9 +3483,8 @@ class GoogleAppsCardV1SelectionInput
       
         # Optional. Text that appears below the selection input field meant to assist
         # users by prompting them to enter a certain value. This text is always visible.
-        # Available for Google Workspace add-ons that extend Google Workspace flows,
-        # which is available as part of the [Gemini Alpha program](https://support.
-        # google.com/a/answer/14170809). Unavailable for Google Chat apps.
+        # Available for Google Workspace add-ons that extend Google Workspace Studio.
+        # Unavailable for Google Chat apps.
         # Corresponds to the JSON property `hintText`
         # @return [String]
         attr_accessor :hint_text
@@ -3908,9 +3896,7 @@ def update!(**args)
       end
       
       # Represents a trigger. Available for Google Workspace add-ons that extend
-      # Google Workspace flows, which is available as part of the [Gemini Alpha
-      # program](https://support.google.com/a/answer/14170809). Unavailable for Google
-      # Chat apps.
+      # Google Workspace Studio. Unavailable for Google Chat apps.
       class GoogleAppsCardV1Trigger
         include Google::Apis::Core::Hashable
       
@@ -3930,9 +3916,8 @@ def update!(**args)
       end
       
       # Represents an action that updates the visibility of a widget. Available for
-      # Google Workspace add-ons that extend Google Workspace flows, which is
-      # available as part of the [Gemini Alpha program](https://support.google.com/a/
-      # answer/14170809). Unavailable for Google Chat apps.
+      # Google Workspace add-ons that extend Google Workspace Studio. Unavailable for
+      # Google Chat apps.
       class GoogleAppsCardV1UpdateVisibilityAction
         include Google::Apis::Core::Hashable
       
@@ -4074,9 +4059,8 @@ class GoogleAppsCardV1Widget
         attr_accessor :divider
       
         # Specifies the event actions that can be performed on the widget. Available for
-        # Google Workspace add-ons that extend Google Workspace flows, which is
-        # available as part of the [Gemini Alpha program](https://support.google.com/a/
-        # answer/14170809). Unavailable for Google Chat apps.
+        # Google Workspace add-ons that extend Google Workspace Studio. Unavailable for
+        # Google Chat apps.
         # Corresponds to the JSON property `eventActions`
         # @return [Array<Google::Apis::ChatV1::GoogleAppsCardV1EventAction>]
         attr_accessor :event_actions
@@ -4107,10 +4091,8 @@ class GoogleAppsCardV1Widget
       
         # A unique ID assigned to the widget that's used to identify the widget to be
         # mutated. The ID has a character limit of 64 characters and should be in the
-        # format of `[a-zA-Z0-9-]+` and. Available for Google Workspace add-ons that
-        # extend Google Workspace flows, which is available as part of the [Gemini Alpha
-        # program](https://support.google.com/a/answer/14170809). Unavailable for Google
-        # Chat apps.
+        # format of `[a-zA-Z0-9-]+`. Available for Google Workspace add-ons that extend
+        # Google Workspace Studio. Unavailable for Google Chat apps.
         # Corresponds to the JSON property `id`
         # @return [String]
         attr_accessor :id
@@ -4172,8 +4154,7 @@ class GoogleAppsCardV1Widget
       
         # Specifies whether the widget is visible or hidden. The default value is `
         # VISIBLE`. Available for Google Workspace add-ons that extend Google Workspace
-        # flows, which is available as part of the [Gemini Alpha program](https://
-        # support.google.com/a/answer/14170809). Unavailable for Google Chat apps.
+        # Studio. Unavailable for Google Chat apps.
         # Corresponds to the JSON property `visibility`
         # @return [String]
         attr_accessor :visibility
diff --git a/generated/google-apis-chat_v1/lib/google/apis/chat_v1/gem_version.rb b/generated/google-apis-chat_v1/lib/google/apis/chat_v1/gem_version.rb
index 383caa93eaa..63a200c640e 100644
--- a/generated/google-apis-chat_v1/lib/google/apis/chat_v1/gem_version.rb
+++ b/generated/google-apis-chat_v1/lib/google/apis/chat_v1/gem_version.rb
@@ -16,13 +16,13 @@ module Google
   module Apis
     module ChatV1
       # Version of the google-apis-chat_v1 gem
-      GEM_VERSION = "0.139.0"
+      GEM_VERSION = "0.140.0"
 
       # Version of the code generator used to generate this client
       GENERATOR_VERSION = "0.18.0"
 
       # Revision of the discovery document this client was generated from
-      REVISION = "20251118"
+      REVISION = "20251207"
     end
   end
 end
diff --git a/generated/google-apis-chat_v1/lib/google/apis/chat_v1/service.rb b/generated/google-apis-chat_v1/lib/google/apis/chat_v1/service.rb
index e1ce3f7a293..045236b3d4b 100644
--- a/generated/google-apis-chat_v1/lib/google/apis/chat_v1/service.rb
+++ b/generated/google-apis-chat_v1/lib/google/apis/chat_v1/service.rb
@@ -716,8 +716,7 @@ def list_spaces(filter: nil, page_size: nil, page_token: nil, fields: nil, quota
         #   Supports changing the [permission settings](https://support.google.com/chat/
         #   answer/13340792) of a space. When updating permission settings, you can only
         #   specify `permissionSettings` field masks; you cannot update other field masks
-        #   at the same time. `permissionSettings` is not supported with `useAdminAccess`.
-        #   The supported field masks include: - `permission_settings.
+        #   at the same time. The supported field masks include: - `permission_settings.
         #   manageMembersAndGroups` - `permission_settings.modifySpaceDetails` - `
         #   permission_settings.toggleHistory` - `permission_settings.useAtMentionAll` - `
         #   permission_settings.manageApps` - `permission_settings.manageWebhooks` - `