Compatibility with RealVNC for Android

I'm using RealVNC on Android to connect to my desktop running Debian Trixie with x0tigervncserver . I encounter multiple issues, all of them related to input handling (like some other ones I've seen: #1992 , #1745 , #1662 , #528 ), so let's summarize them here, and then open separate issues if necessary.

• Sometimes sending an arrow key causes it to be "stuck" until pressed again
• Sending a capital letter in English layout using the "native" Shift (not the Shift in the VNC app) causes Caps Lock to turn on. After this, sending a small letter (only in English layout!) causes Caps Lock to turn off.
• Sending a capital letter in non-English layout the same way (any other way than the VNC app's "Shift") sends a small letter instead. (#528 ?)
• After a while, most keys do not work anymore, displaying "Could not map key event to X11 key code" in the output instead.
• I have Super+T bound to "Open Terminal", and Super+Up to "Maximize Window" (on MATE). Doing this over VNC causes a total mess. Super+T: the terminal opens, but it does not have focus, and I can't figure out what does. Super+Up: does the maximization, but after this, holding Super (even on the physical host keyboard!) causes the window to maximize and unmaximize rapidly until Super is released.

Should I create separate issues for each one of these?

Client (please complete the following information):

• OS: LineageOS 19 (Android 12)
• VNC client: RealVNC
• VNC client version: v3.8.0.48261
• Client downloaded from: Aurora Store

Server (please complete the following information):

• OS: Debian 13.4 Trixie
• VNC server: x0tigervncserver
• VNC server version: 1.16.2
• Server downloaded from: Sourceforge sources, rebuilt for Debian Trixie
• Server was started using: /usr/bin/x0tigervncserver -localhost no -PasswordFile "$HOME/.config/tigervnc/passwd" &>/tmp/tigervnc.log &