The rule to use the Krisp is to select it as mic/speaker from the app. However, there are some apps that do not allow to change the audio settings.
For that, we have a workaround.
1.You need to go to the settings of the apps. and choose Audio settings
2.Then you shall go to Sound settings and choose the App volume & devices information
3.Then you may choose the app or even a tab of the browser where you would like to select Krisp as input and/or output.
And that is it.