The "Browser" source,
the "Control audio via OBS" ("Reroute audio to OBS") property of the source (new Browser source, that can be monitored, will appear in the mixer of OBS),
the "Interact" (right-click over the source) to be able to click inside the browser window.
The Browser source has the hardware acceleration setting in the OBS Advanced Settings, it may or may not work (blank source output).