Element sometimes fails to render display names and reverts to showing the users MXID

### Steps to reproduce

Note, these screenshots are from the customers production environment so I have to redact everything, I appreciate that these screenshots are of limited value. Properly rendered display names and room names redacted in blue, Matrix IDs redacted in red, room/user avatars redacted in black, and messages redacted in green. Unredacted screenshots and logs from Element and Synapse are available in the privately linked support ticket.

The customer does not use GroupSync.

The customer also said:
Q: Does this affect all members of the room at the same time, and for the same users? Does it resolve it self for everyone at the same time? Or is it different for different people?
A: It is not the same for all members or for same users. If I have a user with numeric I get a proper display name as soon as I start writing text in the chat with the user. After one digit it is OK. After restart of App the numeric is back.

The steps to trigger this on a fresh environment are unknown.

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When started typing the names appeared in the right column

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The Matrix IDs shown

After the users responds to the display name reverts back to proper name again

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For this user new posts has correct display name, but old posts doesn't change

Entering crtl + shift + I & ctrl + R, the display name reverts to the MXID

### Outcome

#### What did you expect?

Element to always render peoples display names.

#### What happened instead?

Element sometimes fails to render display names per above screenshots.

### Operating system

Windows 11 Enterprise 23H2, 22631.6199

### Browser information

Edge: Version 142.0.3595.76 (Officiell version) (64 bitar). Chrome: Version 142.0.7444.163 (Officiell version) (64 bitar)

### URL for webapp

N/A

### Application version

Element Web 1.11.108 and 1.11.109. (ESS Classic 25.04 LTS). Both Web/Desktop (unknown version), has not tried mobile

### Homeserver

Synapse v1.129.0-lts.6 and possibly earlier versions of this Synapse LTS that was used in older ESS Classic 25.04 versions

### Will you send logs?

Yes