The desktop update will be pushed to the app but will not be applied before the app is restarted. When a new version is detected and downloaded to the local machine, the app will relaunch automatically to complete the upgrade flow when the system idles for five minutes.
However, active calls or meetings register a leave blocker which will block the upgrade flow, meaning the app won’t close to update if there’s an active call or meeting. The update will wait until the system idles for five minutes with no active calls or meetings before the app is relaunched.
You can check whether a new update is available by clicking on your profile picture in the upper right corner and navigating to About > App version.