What project is affected?
Virtual Assistant and Skill
What language is this in?
TypeScript
What happens?
Using Direct Line, the Virtual Assistant and Skill receives ConversationUpdate Activity by duplicated, sending the welcome message by duplicated as well.
What are the steps to reproduce this issue?
- Deploy a Virtual Assistant or a Skill in TypeScript
- Communicate with the deployed Bot using directline.web
- See the duplicated welcome messages
What were you expecting to happen?
The bot should send an unique welcome message for the user, not for the bot.
Can you share any logs, error output, etc.?
Duplicated welcome message using Web Direct Line Channel

Any screenshots or additional context?
There is a disparity present in the SDK between JS and Dotnet that fixes the issue. See related issue: microsoft/botbuilder-js#3100
Reviewing the TypeScript bots present in BotBuilder-Samples, we noticed that the logic that should be present in the ActivityHandler > dispatchConversationUpdateActivity, is present in the membersAdded event of the bots. See example.