Apple has changed something in 26.4 that causes the host application bundle ID logic to stop working. The XPC connection bundle ID lookup now returns nil which causes the bundle ID to become nil altogether.

This causes a crash in KeyboardKit 10.2.1 and earlier. Make sure to upgrade to KeyboardKit 10.2.2 or later to fix the crash.

KeyboardKit 10.2.2 will however still return nil for the bundle ID. We are looking for a fix, but it may not be doable since it involves private APIs that may have been changed by Apple.

This bug is not isolated to KeyboardKit, but affects all keyboard extensions that use the same kind of logic to resolve the host app bundle ID. For instance, although this thread doesn't explicitly mention the bug, we suspect it's the same problem.

While we look at alternatives, or until Apple issues a fix, developers experiencing this issue should:

• Upgrade to KeyboardKit 10.2.2 or later.
• Implement graceful fallbacks when the bundle ID is empty.
• Avoid relying solely on the host application bundle ID for critical functionality.
• Monitor the GitHub issue for community-discovered workarounds and updates.

We hope to be able to find another way of resolving the bundle ID, and will update this issue with more info. Until then, you should upgrade to KeyboardKit 10.3 and add adjust your app to not rely on the host application information.