Linked Signal Desktop does not delete messages that are deleted on the parent device about signal-desktop HOT 1 CLOSED

Keep Messages is a data storage management feature that was primarily designed for low-end devices where free space can be limited, which is why it's located under "Data and storage" in the Signal Android settings. It was never intended to be a security feature, but it does make it easy for people to quickly free up space on their phone even if their Desktop instance still has plenty of room. You can read more about how and why we developed the feature here:
https://signal.org/blog/storage-management-for-android/

If you want messages to be automatically removed across devices, we recommend setting the default Disappearing Messages timer for chats (under Settings / Privacy). Disappearing message settings are synchronized between linked devices (including Signal Desktop). This blog post goes into a little more detail:
https://signal.org/blog/disappearing-by-default/

Adding support for synchronized message deletion outside of disappearing messages is a potential new feature that we're exploring right now. Even though this isn't a bug, we really appreciate your feedback!

from signal-desktop.