Add search bar on Intercom Messenger

After logging into Intercom, click the Messenger icon at the bottom left to go to your Messenger Home Setting.

Then you'll see "Add apps to your Messenger", click that:

Now, click "Add an app" to add "Zendesk Help Center" app.

Choose "Search bar":

Now you will see a search bar in the Intercom Messenger.

If your Zendesk Help Center has multiple languages, you will see a drop down on the search bar to select a language when searching.

Show search bar on Intercom Messenger

Hint: you can pick a specific language for a search bar widget when adding the widget, and then show this search bar based on the browser language.