New Pin Room Banner: Unavoidable performance and bandwidth issues at high pinned message count.

[CrimsonFork]

Steps to reproduce

Opening a room with hundreds (700-900 in the tested cases) of pinned messages across a long time.

Outcome

What did you expect?

Regular usage without issues.

What happened instead?

Tanked CPU performance, stutter, slow loading of message history for a while, presumably while all the pinned messages are still being fetched. Whether or not a room is encrypted seems to affect little, if anything. Presumably depends on server + client performance and overall bandwidth.

Operating system

OpenSUSE Tumbleweed on an i7-4790

Browser information

Firefox 130.0 (Flatpak)

URL for webapp

app.element.io

Application version

1.11.77

Homeserver

Synapse 1.112.0

Will you send logs?

No

[CrimsonFork]

Didn't have a place to put it in, but it would also generally be nice to have an option not to have the banner while still having access to pins in the sidebar, maybe as a local room setting.