タダです.
AWS マネジメントコンソールに色をつけられるようになったいうアプデがあったと聞いたため自分の手持ちのアカウントで設定してみます.
AWS マネジメントコンソールに色を設定する
マネジメントコンソールにログイン後,Account > Account display settingsから変更ができました.スクリーンショットにあるように変更可能な色は9色あり,この記事では Light Blue を設定しました.

画面上部が Light Blue の色が反映されました.本番アカウントの場合は赤くするなどチーム内で意識しておきたいアカウントは設定するのが良さそうですね.

設定変更に係る権限
マネジメントコンソールの色設定は管理者ユーザーが設定できます.関連のマネージド管理ポリシーとして AWSManagementConsoleAdministratorAccess と AWSManagementConsoleBasicUserAccess が用意されておりどんな権限が設定されているかを確認しておきます.
AWSManagementConsoleAdministratorAccess は以下の権限が設定されています.
{ "Version": "2012-10-17", "Statement": [ { "Effect": "Allow", "Action": [ "uxc:GetAccountColor", "uxc:PutAccountColor", "uxc:DeleteAccountColor", "ec2:DescribeRegions", "notifications:GetFeatureOptInStatus", "notifications:AssociateChannel", "notifications:AssociateManagedNotificationAccountContact", "notifications:AssociateManagedNotificationAdditionalChannel", "notifications:CreateEventRule", "notifications:CreateNotificationConfiguration", "notifications:DeleteEventRule", "notifications:DeleteNotificationConfiguration", "notifications:DeregisterNotificationHub", "notifications:DisableNotificationsAccessForOrganization", "notifications:DisassociateChannel", "notifications:DisassociateManagedNotificationAccountContact", "notifications:DisassociateManagedNotificationAdditionalChannel", "notifications:EnableNotificationsAccessForOrganization", "notifications:GetEventRule", "notifications:GetManagedNotificationChildEvent", "notifications:GetManagedNotificationConfiguration", "notifications:GetManagedNotificationEvent", "notifications:GetNotificationConfiguration", "notifications:GetNotificationEvent", "notifications:GetNotificationsAccessForOrganization", "notifications:ListChannels", "notifications:ListEventRules", "notifications:ListManagedNotificationChannelAssociations", "notifications:ListManagedNotificationChildEvents", "notifications:ListManagedNotificationConfigurations", "notifications:ListManagedNotificationEvents", "notifications:ListNotificationConfigurations", "notifications:ListNotificationEvents", "notifications:ListNotificationHubs", "notifications:ListTagsForResource", "notifications:RegisterNotificationHub", "notifications:TagResource", "notifications:UntagResource", "notifications:UpdateEventRule", "notifications:UpdateNotificationConfiguration", "cloudshell:CreateEnvironment", "cloudshell:CreateSession", "cloudshell:GetEnvironmentStatus", "cloudshell:DeleteEnvironment", "cloudshell:GetFileDownloadUrls", "cloudshell:GetFileUploadUrls", "cloudshell:DescribeEnvironments", "cloudshell:PutCredentials", "cloudshell:StartEnvironment", "cloudshell:StopEnvironment", "cloudshell:ApproveCommand", "q:StartConversation", "q:SendMessage", "q:ListConversations", "q:GetConversation", "q:PassRequest", "resource-explorer-2:AssociateDefaultView", "resource-explorer-2:BatchGetView", "resource-explorer-2:CreateIndex", "resource-explorer-2:CreateView", "resource-explorer-2:DeleteIndex", "resource-explorer-2:DeleteView", "resource-explorer-2:DisassociateDefaultView", "resource-explorer-2:GetAccountLevelServiceConfiguration", "resource-explorer-2:GetDefaultView", "resource-explorer-2:GetIndex", "resource-explorer-2:GetManagedView", "resource-explorer-2:GetView", "resource-explorer-2:ListIndexes", "resource-explorer-2:ListIndexesForMembers", "resource-explorer-2:ListManagedViews", "resource-explorer-2:ListSupportedResourceTypes", "resource-explorer-2:ListTagsForResource", "resource-explorer-2:ListViews", "resource-explorer-2:Search", "resource-explorer-2:TagResource", "resource-explorer-2:UntagResource", "resource-explorer-2:UpdateIndexType", "resource-explorer-2:UpdateView" ], "Resource": "*" } ] }
AWSManagementConsoleBasicUserAccess は以下の権限が設定がされています.
{ "Version": "2012-10-17", "Statement": [ { "Effect": "Allow", "Action": [ "uxc:GetAccountColor", "ec2:DescribeRegions", "notifications:GetFeatureOptInStatus", "notifications:ListManagedNotificationEvents", "notifications:ListNotificationConfigurations", "notifications:ListNotificationEvents", "notifications:ListNotificationHubs", "notifications:GetManagedNotificationChildEvent", "notifications:GetManagedNotificationEvent", "notifications:GetNotificationEvent", "notifications:ListManagedNotificationChildEvents", "cloudshell:CreateEnvironment", "cloudshell:CreateSession", "cloudshell:GetEnvironmentStatus", "cloudshell:StartEnvironment", "cloudshell:DeleteEnvironment", "cloudshell:PutCredentials", "cloudshell:StopEnvironment", "cloudshell:ApproveCommand", "q:StartConversation", "q:SendMessage", "q:ListConversations", "q:GetConversation", "q:PassRequest", "resource-explorer-2:ListIndexes", "resource-explorer-2:Search" ], "Resource": "*" } ] }
まとめ
AWS マネジメントコンソールに任意の色を設定して認識しやすくなるアップデートをさらってみました.