Subtitling plugin

While opening Trados Studio 2021 SR2 - and the version before I get a message saying that Subtitling plugin was created by a third party...

I have to click on OK so it will load.

As far as I can see in the plugin installation page, the plugin was created by the Trados AppStore Team...

Can you kindly explain why this is happening and how to avoid this annoying message?

Thank you,

Pierre Souchar