Dark mode in webkit webview should have dark frame

[fungc-io]

In dark mode, the default frame of the webkit webview should be in dark

RPReplay_Final1716733336.MP4

[fungc-io]

@louischan-oursky,
do we have a default dark theme for the webkit webview frame?

[linear]

DEV-1330 Dark mode in webkit webview should have dark frame

[louischan-oursky]

no