Refreshes the OAuth tokens using the refresh_token grant. Concurrent
callers share a single in-flight request, and tabs on the same origin take
turns through a Web Lock: a tab that waited adopts the tokens the other tab
stored instead of spending a refresh token that has been rotated. An
unrecoverable failure (a 4xx rejecting the refresh token) clears the tokens
and transitions to LOGGED_OUT; transient failures (network, 5xx, rate
limits) leave the session intact and rethrow so the caller can retry. The
resolved tokens omit the refresh token, which core retains internally for
subsequent refreshes.
Refreshes the OAuth tokens using the
refresh_tokengrant. Concurrent callers share a single in-flight request, and tabs on the same origin take turns through a Web Lock: a tab that waited adopts the tokens the other tab stored instead of spending a refresh token that has been rotated. An unrecoverable failure (a 4xx rejecting the refresh token) clears the tokens and transitions toLOGGED_OUT; transient failures (network, 5xx, rate limits) leave the session intact and rethrow so the caller can retry. The resolved tokens omit the refresh token, which core retains internally for subsequent refreshes.