Extension version: 10.3.0
OS: macOS 10.14 (18A391)
The Soapbox extension from Wistia lets you record quick videos + screencasts. It requires you to authenticate with either a Google or Microsoft account, and in the normal flow on Chrome clicking the extension icon presents a sign-in popup, and clicking an account takes you through the onboarding flow.
In Brave, clicking the login buttons takes you through the flow, but then after completing the flow and clicking the extension icon again you’d expect to have already logged in and then start recording a video. However in Brave it just shows the login buttons again.
My best guess is there is some issue sharing cookies between the main browser (where you complete the login/onboarding flow) and the extension’s popup window.