[bug] Multiple app handle functions can crash Tauri, including available_monitors and cursor_position

[XavierF-C]

Describe the bug

I have been using Tauri on a new project for a few months. However, I have noticed that Tauri can crash from time to time. I decided to try to narrow down the possible causes.

Here is a basic program (only the file lib.rs was modified after running pnpm create tauri-app) that can crash on both Windows and Linux, within 1s to 60s:

#[cfg_attr(mobile, tauri::mobile_entry_point)]
pub fn run() {
    tauri::Builder::default()
        .plugin(tauri_plugin_opener::init())
        .invoke_handler(tauri::generate_handler![greet])
        .setup(|app| {
            let app_handle = app.handle().clone();

            tauri::async_runtime::spawn(async move {
                loop {
                    let _handle = app_handle.clone();
                    let func_a = |app_handle: AppHandle| {
                        for _ in 0..1000 {
                            let _ = app_handle.available_monitors();
                        }
                    };
                    let func_b = |app_handle: AppHandle| {
                        for _ in 0..1000 {
                            let _ = app_handle.cursor_position();
                        }
                    };
                    let mut handles = vec!();
                    for _ in 0..10 {
                        let a_handle = app_handle.clone();
                        let b_handle = app_handle.clone();
                        handles.push(std::thread::spawn(move || {func_a(a_handle)}));
                        handles.push(std::thread::spawn(move || {func_b(b_handle)}));
                    }

                    for (_i, h) in handles.into_iter().enumerate() {
                        let _ = h.join();
                    }
                }
            });

            Ok(())
        })
        .run(tauri::generate_context!())
        .expect("error while running tauri application");
}

Basically, the functions available_monitors and cursor_position are not thread safe. There might be other problematic functions, but I have only tested those. The crashes are more frequent when func_a and func_b are called, but can occur with only func_a or func_b.

Thanks in advance.

Reproduction

The error can occur both in debug or release mode. Here is an example:

1. pnpm install
2. pnpm tauri build --debug --no-bundle
3. ./src-tauri/target/debug/crashtauri

Here is the project (without node_modules or release folders):
crashtauri.zip

Expected behavior

The functions called from app.handle should not cause the program to crash.

Full tauri info output

[✔] Environment
    - OS: Linux Mint 22.2.0 x86_64 (X64) (cinnamon on x11)
    ✔ webkit2gtk-4.1: 2.48.7
    ✔ rsvg2: 2.58.0
    ✔ rustc: 1.90.0 (1159e78c4 2025-09-14)
    ✔ cargo: 1.90.0 (840b83a10 2025-07-30)
    ✔ rustup: 1.28.2 (e4f3ad6f8 2025-04-28)
    ✔ Rust toolchain: stable-x86_64-unknown-linux-gnu (default)
    - node: 22.21.1
    - pnpm: 10.20.0
    - npm: 10.9.4

[-] Packages
    - tauri 🦀: 2.10.3
    - tauri-build 🦀: 2.5.6
    - wry 🦀: 0.54.4, (outdated, latest: 0.55.0)
    - tao 🦀: 0.34.8, (outdated, latest: 0.35.0)
    - @tauri-apps/api  ⱼₛ: 2.10.1
    - @tauri-apps/cli  ⱼₛ: 2.10.1

[-] Plugins
    - tauri-plugin-opener 🦀: 2.5.3
    - @tauri-apps/plugin-opener  ⱼₛ: 2.5.3

[-] App
    - build-type: bundle
    - CSP: unset
    - frontendDist: ../dist
    - devUrl: http://localhost:1420/
    - framework: React
    - bundler: Vite

Stack trace

Multiple errors can occur. For examples: 
Aborted (core dumped)
or
Segmentation fault (core dumped)
or
malloc(): unaligned fastbin chunk detected
Aborted (core dumped)

Additional context

No response