This is a brute force approach to support "context blocks" without taking any steps backwards (i.e., it supports older transactions and newer, modular transactions), but it feels like this is a lot of steps sideways and this change would be far better if it took a nuanced approach through T12921.

When users are @mentioned on an object, render their name in a disabled style if they've been muted.

See also T13068, which suggests rendering mentions in a special style when the user has muted the object.

This presumably worked. T12404 survives it, but that task captures everything remaining here.

• T12921 is adjacent to mail rendering.
• T13439 mentioned the hovercard summary text.

D21574 implements the hovercard and summary length changes.

It appears that PHUICircleView no longer exists, so calling this moot.

See T13602 for modern followup, recent changes, and plans.

I think this was at least approximately resolved by D21115, which made the default log much quieter and the "debug" log more verbose.

Seems okay for me, too. Calling this resolved, thanks for the report!

That covered everything that looked low-hanging.

From "--trace", client PHID generation seems to be the limiting factor.

A minimal implementation here is probably:

See T13612 for followup.

Continued in T13612.

See T13602 for eventual followup.

I'm going to close this in favor of T13602, which has a more cohesive/modern discussion of the issue. Broadly:

Ah! I like that fix, and it also works for me locally. I think the protocol-length-limit is reasonable to retain on the basis of general sanity, but I'll add the negative lookbehind to further encourage PCRE to run in something resembling O(N) time.