Upgrading un-Encrypted & public Matrix rooms result in the room becoming E2EE with no input requested from the upgrader

[jahway603]

Description

After upgrading an un-Encrypted & public Matrix room, the result is the room becoming E2EE with no input requested from the upgrader & since encryption is turned on (and can never be turned off), this results in breaking any bots bridging to other services as those bridges require that the room remain un-Encrypted for those bots to continue bridging the other services to the Matrix chat room.

There is nothing prompting the person running /upgraderoom <version-number> if they want to keep the room un-Encrypted or to force encryption, so I propose a flag be added to the /upgraderoom command to do this.

This issue is similar to Issue #9246, but that issue does not provide any solutions. This bug was discovered when a community member upgraded a Matrix room and it broke the bridge bot due to this "uncommon" (classified by @DMRobertson) bug.

Steps to reproduce

• Create a new Matrix room that is (1) public, (2) NOT encrypted, and (3) this specific server creates a room with version 5
• Run the /upgraderoom 9 in this room and follow the prompts
• The resulting room is not E2EE when this is not the desired behavior as the upgrader wanted to upgrade their un-Encrypted room

Homeserver

matrix.lrn.fm

Synapse Version

1.67.0

Installation Method

I don't know

Database

No clue as not server admin

Workers

I don't know

Platform

No clue as not server admin

Configuration

No clue as not server admin

Relevant log output

No clue as not server admin

Anything else that would be useful to know?

No response

[jahway603]

Would this Issue need to be included in Issue matrix-org/matrix-spec#456 ?

[clokep]

Duplicate of #9246, I believe.

[clokep]

Would this Issue need to be included in Issue matrix-org/matrix-spec#456 ?

No, this is an implementation bug.