IO Manager: Lock writes on a tag's details stops every write to that tag from reaching the device, while the tag keeps reading. A locked tag is marked in the tag list. Unlock it to send writes again.
IO Manager: a tag's details have an Enable or Disable button, so you can switch one tag on or off without selecting it in the tag list.
PulseAudio: playing audio on a speaker whose Play tag has writes locked is refused instead of played.
Bug Fixes
OPC UA: server tags that clients only read are advertised as read-only, and a client that writes one gets Bad_NotWritable. The value other clients read does not change.