Enable spaces by default.

[clokep]

This enables the experimental spaces flag by default.

Questions

• Do we want to do this for the multi-SSO providers and busy presence?
• Are there things we want to move behind a different flag (maybe the restricted rooms parts)?

[clokep]

@callahad Is this what you had in mind from our conversation earlier?

[callahad]

Sorry for the delay; needed to mull some things over.

Functionally, yes, I think this is what we want.

Since we're turning on spaces_enabled by default, I think we should also have it appear in the sample config (and docs, if there's an obvious place?) with an explanation of what it does. Which, to the best of my knowledge, is currently:

1. Enables the Spaces Summary API (MSC2946)
2. Enables restricting room membership based on space membership (MSC3083) (and thus the org.matrix.msc3083 experimental room version)

We should probably have a brief discussion before adding any additional MSCs under the spaces_enabled flag. I'm not sure a priori what the right bias is there, so we can park it until there's a specific proposal.

[clokep]

Enables restricting room membership based on space membership (MSC3083) (and thus the org.matrix.msc3083 experimental room version)

This is maybe worth including, but I'm hesitant to talk about experimental room versions too loudly since they break in horrible ways when you remove them (see #7083).

We should probably have a brief discussion before adding any additional MSCs under the spaces_enabled flag. I'm not sure a priori what the right bias is there, so we can park it until there's a specific proposal.

I don't think there's any plans to implement more at the moment?

I'll add some documentation.

Unfortunately neither of the questions from the description were answered. Could you take another look @callahad?

[callahad]

I don't think there's any plans to implement more [Spaces MSCs] at the moment?

None that I'm aware of, but I could imagine something coming down the pike like
MSC2962: Managing power levels via Spaces or MSC3189: Per-room/per-space profile data and it seeming natural to toss it under spaces_enabled

Unfortunately neither of the questions from the description were answered. Could you take another look @callahad?

I somehow skimmed over those, thanks for drawing attention back to those :)

• Do we want to do this for the multi-SSO providers and busy presence?

I'll raise it with Product and have a concrete response by this time next week

• Are there things we want to move behind a different flag (maybe the restricted rooms parts)?

What do you think? MSC2176: Update the redaction rules defines a org.matrix.msc2176 room version which is currently enabled by default, but otherwise we just provide V1-6.

[clokep]

• Do we want to do this for the multi-SSO providers and busy presence?

I'll raise it with Product and have a concrete response by this time next week

I think we can keep this PR just about spaces then, we can handle those separately.

• Are there things we want to move behind a different flag (maybe the restricted rooms parts)?

What do you think? MSC2176: Update the redaction rules defines a org.matrix.msc2176 room version which is currently enabled by default, but otherwise we just provide V1-6.

I actually meant more specifically to spaces, if there's bits which we shouldn't expose by default yet. I think it is probably fine as is, since the restricted join rules stuff requires using an experimental room version.

[anoadragon453]

We may want to leave a note here stating that we only include experimental features that are on by default in the sample config.

[clokep]

Is that true though? This only includes the one enabled by default, but I'm unsure that's the reason it is the only one included.

[clokep]

I'm going to merge this as is for now, we can update it when (if?) we add more here.

[anoadragon453]

Code looks good to me, and I think we've nailed down what other features we'd like to include here now.