If you are using latest NVDA alpha snapshot, this is an important notice (for others, you can ignore it, or you can take a note of the following notice):
An issue was discovered with some of my add-ons where after installing add-on updates, NVDA will not restart properly, playing a critical error tone instead. The issue had to do with install tasks procedure, and was traced to an incomplete module import due to a recent change to NVDA alpha snapshots.
The following add-ons are affected:
Note: for StationPlaylist and Windows 10 App Essentials, development snapshots are also affected.
To mitigate this, I’m releasing an emergency patch for these add-ons tonight (my time):
For StationPlaylist and Windows 10 App Essentials, an additional build will be created for development snapshot users (dated April 28, 2020).