I recently updated to Flutter version 1.3.8, after updating the auto completion on VSCode stopped working. However, this was working before the update.

My flutter doctor:
Doctor summary (to see all details, run flutter doctor -v):
[✓] Flutter (Channel unknown, v1.3.8, on Mac OS X 10.14.2 18C54, locale en-CA)
[✓] Android toolchain - develop for Android devices (Android SDK version 28.0.3)
[✓] iOS toolchain - develop for iOS devices (Xcode 10.1)
[✓] Android Studio (version 3.1)
[✓] IntelliJ IDEA Ultimate Edition (version 2018.2.4)
[✓] VS Code (version 1.32.3)
[!] Connected device
! No devices available