Crashes when typing "U" or "u" in the "Start New Chat" user search

[omerbustun]

Steps to reproduce

1. Open Element Desktop
2. Click the "+" button to start a new chat.
3. In the search field, type the letter "U" or "u".

We are running an on-prem Synapse server for internal company communications and have deployed Element Desktop on client machines. On some clients, when trying to start a new chat by clicking the “+” button and searching for a user, typing "U" or "u" causes Element Desktop to crash immediately. This issue does not occur when searching for a word that contains "u" but does not start with it.

Outcome

What did you expect?

The search should function normally and display results for users whose names start with or contain "U" or "u".

What happened instead?

• The application crashes instantly without any visible delay.
• No API request is sent to the Synapse server before the crash.
• Running the same directory search query via curl works fine, confirming the issue is not server-side.

When started via terminal (element-desktop --verbose --enable-logging), the following lines are printed a while after the crash.

<--- Last few GCs --->

[1:0x2a0800370000]    73461 ms: Scavenge (interleaved) 4058.9 (4065.0) -> 4058.3 (4075.5) MB, pooled: 0 MB, 15.91 / 0.00 ms  (average mu = 0.210, current mu = 0.185) allocation failure; 
[1:0x2a0800370000]    77258 ms: Mark-Compact (reduce) 4058.8 (4075.5) -> 4058.6 (4061.2) MB, pooled: 0 MB, 3097.63 / 0.07 ms  (+ 15.1 ms in 0 steps since start of marking, biggest step 0.0 ms, walltime since start of marking 3125 ms) (average mu = 0.206, 

<--- JS stacktrace --->

[155936:0210/144640.014494:ERROR:v8_initializer.cc(805)] V8 javascript OOM (Ineffective mark-compacts near heap limit).
Renderer process crashed - see https://www.electronjs.org/docs/tutorial/application-debugging for potential debugging information.

Operating system

Ubuntu 24.04.1, Windows 11

Application version

Element version: 1.11.91 Crypto version: Rust SDK 0.8.0 (21f7cc7), Vodozemac 0.8.1

How did you install the app?

From the Element repo

Homeserver

Private Synapse homeserver (v. 1.121.1)

Will you send logs?

No