deeplink is not working in teams tab

ChrisWebbTech 

thank you for your reply

i did follows:

(1) make a webpage with two deeplink to a chat.
first deeplink(with target="_blank") https://teams.microsoft.com/l/chat/0/0?users=test@example.com
second deeplink(without target="_blank") https://teams.microsoft.com/l/chat/0/0?users=test@example.com
(2) create this webapp to teams channel tab names 'myapp' with url like as https://example.com
(3) clicked 'myapp' tab, the webpage will be show in teams and two deeplink can clickable
(4) clicked first deeplink(with target="_blank"), a browser will started outside teams and show a page as screen1
(5) clicked the last link, teams chat will be start.
(6) clicked second deeplink(without target="_blank"), theams can be show a page as screen2
(7) clicked the last link, teams chat can not be start(no any response).

our client don't like to start a chat must be open a new tab throught a browser.
they want do anythin inside teams only.

is any way to resolve this?

screen1screen2