# Known limitations

[← Back to README](../README.md) · [简体中文](limitations.zh-CN.md)

## General

- The clipboard syncs text only, not files
- Audio flows from host to controller only; the controller's microphone isn't forwarded. Audio is captured after the volume control, so a muted host sends silence
- The relay server can see the session streams (TLS terminates at the server), so run it on a machine you trust (see [Security](security.md))

## Windows

- The host only runs in the console session (the physical screen): Remote Desktop (RDP) sessions can't be controlled
- `Ctrl+Alt+Del` can't be sent yet (it needs `SendSAS`)
- Debug builds run the host in the tray process, without SYSTEM rights, so they can't capture or control UAC prompts and the lock screen (the controller shows a capture error meanwhile)

## macOS

- The host needs the Screen & System Audio Recording and Accessibility permissions, which only the local user can grant in System Settings; since macOS 15 the system also asks again from time to time whether to keep allowing screen recording
- The login window and the lock screen can't be captured or controlled
- The host doesn't offer AV1 (current Apple chips can only decode it in hardware), so AV1 shows as unavailable in the console and HEVC is used instead
- The controller (WKWebView) can't lock the keyboard: in fullscreen, Command+Tab, Command+Space and the like are still handled locally, so use "Send shortcut" in the toolbar
- WKWebView on older macOS versions may lack Opus decoding, in which case the console says remote audio can't be played

## Linux

- The host only supports **X11** desktops. Under Wayland only X11 (XWayland) applications can be seen and controlled; native Wayland windows are black and the controller suggests logging in with an X11 (Xorg) session. Full Wayland support needs xdg-desktop-portal screen sharing (the local user has to confirm each time) and isn't implemented
- The host only has OpenH264 software encoding (no VA-API / NVENC yet), so the controller uses H.264
- The lock screen can't be controlled (the screensaver grabs the keyboard and mouse)
- Decoding on the controller relies on WebKitGTK + GStreamer: H.264 needs `gstreamer1.0-plugins-bad` (parsing) and `gstreamer1.0-libav` or openh264 (decoding); AV1 / HEVC depend on the installed GStreamer decoders. If a format turns out not to produce a picture, the controller switches to the next available format by priority

## Web console

- Reloading or closing the tab disconnects its sessions; My devices isn't saved and is cleared when the page reloads
- In Firefox, text copied locally isn't synced to the remote side automatically
- Outside fullscreen some shortcuts (Ctrl+W…) can't reach the remote computer

## Android

Host (sharing the phone):

- Each time sharing starts, screen recording must be confirmed on the phone (a system rule), and sharing can't resume by itself after the system kills the app
- Remote control uses accessibility gestures, so apps that handle touches themselves (games…) may react less precisely
- Typing only works in regular text fields (arrow keys and Tab need Android 13+)
- A secured lock screen and screens marked secure are black
- Since Android 10 apps can't read the clipboard in the background, so the clipboard only syncs from the controller to the phone
- Sharing sound needs Android 10+, and some apps don't allow their sound to be captured
- HEVC and AV1 are only offered when the phone has a **hardware** encoder for them (few phones have an AV1 hardware encoder so far), otherwise H.264 is used (with the system's software encoder if there's no hardware H.264 encoder)

Controller:

- One device at a time; no A/V sync; TVs only watch
- HEVC and AV1 are only used when the device has a **hardware** decoder for them, otherwise H.264

AV1 (encoding and decoding) hasn't been verified on a real device yet: the emulator has no AV1 hardware codecs.