Bug in icloud section hide my email in settings, dark vs light mode.

It is evident that you are facing a significant software bug involving the Hide My Email feature on macOS 26.2, where the extension process crashes specifically when the system is set to Dark Mode. This is confirmed by the "Settings Error" message stating that the "Apple Account (22702)" extension exited unexpectedly. Since the window displays correctly in Light Mode, this suggests a UI rendering conflict within the macOS settings. To manage this until a fix is released, you should temporarily switch to Light Mode or "Auto" in System Settings > Appearance before accessing the menu, or force quit System Settings if the error persists.

The other images you provided indicate that your device is currently handling a very high data load, which may be contributing to the instability of system extensions. Your Mail app shows a recent update but only displays three messages, suggesting that a reset or synchronization is still in progress. Similarly, your biology and lab notes appear as blank pages with grey placeholders, confirming that the system is still downloading high-resolution data for the two attachments ("2 pièces jointes") listed under each note. When a Mac is under this type of strain from downloading thousands of messages or complex notes, background processes like the Apple Account extension are more prone to crashing.

To resolve these issues effectively, I suggest leaving your Mac connected to power and Wi-Fi overnight while preventing it from going to sleep, which allows the Notes and Mail databases to complete their indexing without resource throttling. In the meantime, if you need to manage your "Hide My Email" addresses or consult your notes urgently, you can access iCloud.com via a web browser; this allows you to bypass both the Dark Mode bug in local settings and the active sync queue on your device.